Ultimate Chocolate Peanut Butter Sheet Cake: Your Easy Guide to a Crowd-Pleasing Dessert

Chocolate Peanut Butter Sheet Cake – a truly delightful creation featuring a soft, incredibly moist dark chocolate cake base, generously topped with a luscious, creamy, and nutty peanut butter frosting, all finished with a smooth, glistening dark chocolate ganache. Baked in a convenient 9×13 inch pan, this cake is designed for effortless serving and sharing, making it the perfect dessert for any gathering, big or small!

Peanut butter enthusiasts, prepare yourselves for an extraordinary treat! This incredible peanut butter sheet cake recipe is about to become your new obsession. I’ll admit, peanut butter isn’t typically my go-to flavor; it’s quite calorie-dense and can often dominate other ingredients. However, as a food blogger, creating diverse and delicious recipes, even those outside my personal favorites, is part of the journey. And let me tell you, I truly believe I’ve outdone myself with this particular creation.

The secret to its success lies in the balance. The robust, deep flavor of the dark chocolate cake batter perfectly complements and harmonizes with the rich, creamy peanut butter frosting. This ensures that neither flavor overpowers the other, resulting in a symphony of tastes that will delight your palate. Furthermore, I absolutely adore preparing this cake in a 9×13 inch pan. Sheet cakes are known for their exceptional moistness, and this one is no exception. It’s incredibly simple to bake, a breeze to frost, and remarkably easy to slice and serve, making it an ideal choice for any occasion. This straightforward cake recipe is guaranteed to be a hit, leaving everyone, especially the kids, clamoring for an extra slice!

So, gather your ingredients, clear your countertop, and get ready to bake this phenomenal Chocolate Peanut Butter Sheet Cake. It’s time to bring some magic to your kitchen!

For more delightful and easy cake recipes, be sure to check out these irresistible options:

• The Most Delicious Lemon Pistachio Cake Recipe
• Best White Chocolate Raspberry Bundt Cake Recipe
• Easy Copycat Hostess Ding Dong Cake Recipe
• Copycat Chocolate Mousse Cheesecake Factory

Why You Need to Make This Chocolate Peanut Butter Sheet Cake

1. The Irresistible Chocolate & Peanut Butter Combo – Even if you’re like me and not typically a huge fan of overwhelming peanut butter flavor, this recipe will change your mind. The deep, slightly bitter notes of dark chocolate create a phenomenal balance with the creamy, salty-sweet peanut butter. It’s a classic pairing for a reason, reminiscent of your favorite candy bar but elevated into a sophisticated and incredibly satisfying dessert. This duo creates a flavor profile that is truly addictive.
2. Remarkable Texture – This isn’t just any cake; it’s a super moist cake that you won’t be able to resist. The peanut butter in the frosting, combined with the carefully crafted chocolate cake batter, contributes to a rich, dense, yet wonderfully tender crumb. Every bite offers a delightful contrast between the smooth ganache, creamy frosting, and the soft, melt-in-your-mouth cake. Prepare to fall in love with its luxurious texture.
3. Effortless Sheet Pan Perfection – Sometimes, the grandeur and fuss of a layer cake just isn’t what you need. Enter the sheet cake: your unbothered queen of desserts! This recipe, baked in a simple 9×13 inch pan, offers all the flavor with none of the stacking stress. It’s perfect for potlucks, family dinners, or any occasion where you need to feed a crowd without spending hours on intricate decoration. Easy to transport, easy to slice, and always a crowd-pleaser!
4. Budget-Friendly & Accessible Ingredients – I often find myself annoyed when a recipe calls for obscure, expensive ingredients that require a special trip to a gourmet store. This chocolate peanut butter sheet cake uses readily available ingredients that are likely already in your pantry or easily found at any local grocery store. Despite its simplicity and affordability, this cake tastes anything but basic – it’s truly one of the best and most comforting cakes you’ll ever try.

Essential Grocery List – Chocolate Peanut Butter Sheet Cake

To make this amazing cake, here’s a breakdown of the key wet and dry ingredients. For a full, detailed list of measurements, please refer to the comprehensive recipe card at the bottom of this page!

Peanut Butter: This creamy peanut butter frosting is a dream come true for all peanut butter lovers. It’s often compared to a Reese’s cup, but I promise you, it’s so, so, so much better! For the best results in your frosting, make sure to use a smooth, full-fat creamy peanut butter, like Skippy or Jif. Natural peanut butter, while delicious, can sometimes separate or have a grittier texture that might affect the smoothness of your buttercream.

• Vanilla Extract: High-quality vanilla extract is a game-changer. My personal recommendation for this recipe is Nielsen-Massey’s vanilla extract. It delivers a rich, authentic vanilla flavor that truly elevates the overall taste of both the cake and the frosting, adding a wonderful aromatic depth.
• Chocolate Chips: The quality of your chocolate chips directly impacts the richness of your dark chocolate ganache. Don’t skimp here! Investing in good quality semi-sweet chocolate chips (or chopped baking chocolate) will transform your ganache from merely “okay” to absolutely “wow!” It melts smoother and provides a more intense chocolate flavor.
• White Granulated Sugar: A baking staple! We go through an enormous amount of sugar in my kitchen, so it’s always at the top of my must-buy list. Granulated sugar provides essential sweetness, moisture, and also contributes to the cake’s tender texture.
• Baking Soda & Baking Powder: These are your leavening agents, crucial for giving the cake its light and airy structure. For optimal results, make sure you’re getting fresh baking soda and baking powder regularly, ideally monthly. Expired leavening agents can lead to a dense, flat cake.
• Large Eggs: Always use large eggs for consistent baking results. It’s vital that your eggs are at room temperature. Room temperature eggs emulsify better with other ingredients, creating a smoother, more uniform batter and a lighter, more tender cake.
• Unsalted Butter: Just like the eggs, your unsalted butter should be at room temperature for both the cake batter (if applicable, though this is a oil-based cake) and especially for the peanut butter buttercream. Softened butter creams beautifully with peanut butter and powdered sugar, resulting in an incredibly smooth, fluffy, and perfectly textured frosting. Using unsalted butter allows you to control the exact amount of salt in your recipe.
• All-Purpose Flour: The structural backbone of our cake. Sifted all-purpose flour ensures a fine, lump-free base, contributing to the cake’s delicate crumb.
• Buttermilk: This acidic ingredient reacts with the baking soda to create lift and also adds incredible moisture and tenderness to the chocolate cake, enhancing its flavor profile. Ensure it’s at room temperature for optimal mixing.
• Hot Water: Dissolving cocoa powder in hot water (or coffee) intensifies the chocolate flavor, making the cake exceptionally rich and dark.
• Vegetable Oil: Using vegetable oil instead of butter in the cake batter helps to ensure a consistently moist cake, as oil remains liquid at room temperature, unlike butter.
• Heavy Whipping Cream: Essential for both the silky smooth peanut butter buttercream and the decadent chocolate ganache. Its fat content provides richness and helps achieve the desired creamy consistency.
• Salt: A small but mighty ingredient! Salt balances the sweetness in both the cake and the frosting, enhancing all the other flavors.

Step-by-Step Guide to the Perfect Chocolate Cake Batter

This one-bowl, no-fuss method results in what many consider the best chocolate cake you’ll ever taste, and it’s easier than you think! Follow these essential tips to achieve a flawless batter every time:

• Room Temperature Matters: Ensure your eggs and buttermilk are at room temperature. This isn’t just a suggestion; it’s crucial for better emulsification. Room temperature ingredients blend more smoothly and evenly, preventing lumps and creating a homogenous batter that bakes into a uniformly textured and tender cake. Cold ingredients can cause the batter to seize, resulting in a denser final product.
• Sift for Success: Always sift your dry ingredients together. This includes flour, cocoa powder, baking soda, baking powder, and salt. Sifting helps to break up any clumps, ensuring a light and airy texture. More importantly, it evenly distributes the leavening agents throughout the dry mixture, which is essential for consistent rise and preventing dense spots in your cake.
• Thoroughly Combine Wet Ingredients: In a separate bowl, whisk your wet ingredients—eggs, buttermilk, hot water, vegetable oil, and vanilla extract—until they are fully and evenly combined. This step ensures that all the liquid flavors and components are uniformly dispersed before they meet the dry mix, contributing to a harmonious taste and texture.
• Mix Gently, Avoid Overmixing: When combining the liquid ingredients with the dry, pour the wet mixture slowly into the dry and mix gently, just until combined. Use a whisk initially, then switch to a rubber spatula. Overmixing develops the gluten in the flour too much, leading to a tough, dry cake. You’re looking for a smooth batter with no visible streaks of flour, but don’t beat it vigorously.
• Scrape the Bowl: After initial mixing, always use a rubber spatula to scrape down the bottom and sides of your mixing bowl. This ensures that all ingredients, especially any dry pockets that might cling to the bottom, are fully incorporated into the batter, leading to a perfectly consistent cake.
• Evenly Spread the Batter: Once your batter is ready, transfer it to your prepared cake pan. Use a spatula or the back of a spoon to spread the batter evenly across the bottom of the pan. This step is crucial for uniform baking, guaranteeing that your finished cake has an even thickness and bakes through properly without raw or overcooked spots.
• Monitor Baking Time & Test for Doneness: Keep a close eye on the baking time, as oven temperatures can vary. The best way to check for doneness is by inserting a toothpick into the center of the cake. It should come out with just a few moist crumbs attached, indicating that the cake is fully baked but still delightfully moist. If it comes out wet, continue baking for a few more minutes; if it comes out completely clean, it might be slightly overbaked.

Expert Tips for a Flawless Peanut Butter Buttercream

Don’t let the thought of making buttercream intimidate you! With these tips and tricks, you’ll whip up a smooth, delicious peanut butter frosting effortlessly. For a complete list of instructions, scroll down to the recipe card below!

• Room Temperature Butter & Peanut Butter: This is paramount for a smooth, lump-free frosting. Ensure both your unsalted butter and creamy peanut butter are at true room temperature. If they are too cold, they won’t cream together properly, resulting in a lumpy, inconsistent frosting. Softened, but not melted, is the goal.
• Whip Until Light and Fluffy: In your electric mixer fitted with a paddle attachment, truly beat the butter and peanut butter together. This creaming process incorporates air, making the frosting wonderfully light and fluffy. Aim for about 2-3 minutes on medium-high speed until the mixture is visibly pale and airy. Don’t rush this step!
• Gradual Addition of Dry Ingredients: When adding powdered sugar, vanilla extract, salt, and heavy whipping cream, start with the mixer on the lowest speed. This prevents a “sugar cloud” from erupting in your kitchen! Gradually incorporate the powdered sugar, one cup at a time, allowing it to fully mix before adding more. Once all the dry ingredients are mostly combined, increase the mixer speed to medium and beat for about 3 minutes until the frosting is incredibly smooth, creamy, and well-aerated.
• Scrape Down the Bowl (Again!): Just like with the cake batter, it’s essential to periodically stop your mixer and scrape down the sides and bottom of the bowl with a rubber spatula. This ensures that all ingredients are fully incorporated, and you don’t end up with unmixed pockets of sugar or butter. Give the frosting one final mix with the spatula to push out any large air bubbles after beating.
• Adjusting Consistency for Perfection: Frosting consistency is key. If your buttercream is too thick, add more heavy cream, one teaspoon at a time, until you reach your desired spreading or piping consistency. If it’s too thin, gradually add more powdered sugar, one tablespoon at a time, until it thickens up. It’s much easier to add small amounts than to try and fix an overly wet or stiff frosting.

Essential Tools for This Recipe

Having the right tools can make all the difference in your baking experience. Here’s a list of the equipment I recommend and used to create this delicious Chocolate Peanut Butter Sheet Cake:

• Mixing Bowls:You’ll need at least two good-sized mixing bowls for combining your dry and wet ingredients separately before mixing them together.
• Whisk:An essential tool for whisking together wet ingredients, ensuring a smooth and lump-free mixture, and for gently combining dry ingredients.
• Sifter: Crucial for sifting dry ingredients like flour, cocoa powder, baking soda, and baking powder. This removes lumps and aerates the mixture, resulting in a lighter cake texture.
• Electric Mixer with Paddle Attachment: Indispensable for creaming the butter and peanut butter to achieve that perfect fluffy consistency for the frosting, as well as thoroughly mixing the frosting ingredients. A stand mixer is ideal, but a good hand mixer will also work.
• Rubber Spatula: A baker’s best friend! Essential for scraping down the sides of the mixing bowl, ensuring all ingredients are fully incorporated, and gently folding batter or frosting.
• Offset Spatula: This tool makes spreading frosting smoothly and evenly over your sheet cake incredibly easy. It’s also great for leveling batter in the pan.
• Piping Bag and Decorating Tip (such as Wilton 8B): For adding an elegant decorative border around the edge of your cake with the peanut butter buttercream, giving it a professional finish.
• Cake Pan (9×13 inches): The star of the show! A sturdy metal 9×13 inch pan is perfect for baking this sheet cake evenly.
• Parchment Paper: Absolutely essential for lining your cake pan. It prevents sticking, makes removing the cooled cake a breeze, and ensures easy cleanup.
• Microwave-Safe Bowl:Useful for melting chocolate and heating cream when preparing the ganache.
• Measuring Cups and Spoons: Accurate measurements are fundamental to successful baking, so make sure you have a reliable set.

Frequently Asked Questions About Chocolate Peanut Butter Sheet Cake

Can I use natural peanut butter instead of creamy peanut butter for the frosting?

While natural peanut butter is a healthier option, it tends to have a different consistency due to oil separation and can be grittier than conventional creamy peanut butter. This difference may significantly affect the texture and stability of your frosting, making it less smooth and potentially runnier. For the best, silkiest buttercream results, I highly recommend sticking with smooth, full-fat creamy peanut butter like Skippy or Jif. If you insist on using natural, ensure it’s very well stirred, and you may need to adjust the amount of powdered sugar to achieve the right consistency.

Can I make the cake ahead of time?

Absolutely! This cake is wonderfully make-ahead friendly. You can bake the chocolate cake layer up to two days in advance. Once fully cooled, wrap it tightly in plastic wrap and store it at room temperature. I even suggest baking the cake one day and then preparing the frosting and ganache and assembling on the second day. This breaks up the work, making the entire process much less overwhelming and more enjoyable!

How can I ensure my chocolate ganache is perfectly smooth?

The key to a silky ganache is patience and quality ingredients. Use good quality chocolate chips or finely chopped baking chocolate. Heat your heavy cream until it’s steaming and just barely bubbling around the edges, but don’t let it boil vigorously. Pour the hot cream over the chocolate, and crucially, let it sit undisturbed for 5 minutes. This allows the heat from the cream to melt the chocolate thoroughly. After 5 minutes, gently stir from the center outwards until completely smooth. Avoid whisking vigorously, which can incorporate air and make the ganache dull.

Can I omit the chocolate ganache or use a different topping?

While the chocolate ganache adds an extra layer of decadence and beautiful shine, you can certainly customize your cake. If you prefer to omit it, the peanut butter buttercream alone is delicious! Alternatively, you could sprinkle the top with chopped roasted peanuts, mini chocolate chips, or even a drizzle of melted chocolate without making a full ganache. The cake will still be fantastic!

Storing and Freezing – Chocolate Peanut Butter Sheet Cake

To properly store your delightful Chocolate Peanut Butter Sheet Cake and maintain its freshness, place it in an airtight container. If you don’t have one large enough, cover the entire cake tightly with plastic wrap to prevent it from drying out or absorbing other refrigerator odors. Due to the presence of both the rich peanut butter frosting and the luscious chocolate ganache, this cake should be stored in the refrigerator. When properly stored, it will remain fresh and delicious for up to 3-4 days. For the best taste and texture, allow the cake to come to room temperature for about 30 minutes before serving.

Freezing – Chocolate Peanut Butter Sheet Cake

If you want to extend the life of your Chocolate Peanut Butter Sheet Cake, it freezes beautifully! First, ensure the cake has cooled completely and the ganache has fully set. For individual servings, slice the cake into squares before freezing. Wrap each slice (or the entire cake, if freezing whole) tightly in at least two layers of plastic wrap, followed by a layer of aluminum foil. This double-layer protection is crucial to prevent freezer burn and preserve its moisture and flavor. Place the wrapped cake or slices in a freezer-safe container or a large resealable plastic bag, and don’t forget to label it with the date. The cake can be frozen for up to 2-3 months. To enjoy, thaw the cake overnight in the refrigerator, then let it sit at room temperature for about 30 minutes before serving for optimal taste and texture.

Looking for more delightful recipes that feature the magic of peanut butter or decadent chocolate? Here are some other favorites you’re sure to love!

• The Best Peanut Butter Brookies
• No Bake Peanut Butter Chocolate Pie
• The Best Peanut Butter Oreo Cookies

Remember, if you adore this recipe or have any questions, please LEAVE A 5-STAR REVIEW AND A COMMENT below! Your feedback means the world to me. For more fun baking adventures and daily inspiration, follow me on Instagram, Pinterest, and TikTok. I share so many exciting things across all my platforms!

Recipe

Chocolate Peanut Butter Sheet Cake

Molly Murphy

This recipe delivers a soft and moist dark chocolate cake topped with a creamy, nutty peanut butter frosting, finished with a luscious dark chocolate ganache. Made in a 9×13 inch pan, it’s perfect for easy serving at any gathering!

5 from 4 votes

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Course Dessert

Cuisine American, Cake

Servings 16 Squares

Ingredients

For the chocolate cake

• 3 large eggs (room temperature)
• 1 cup buttermilk (room temperature)
• 1 cup hot water
• ½ cup vegetable oil
• 1 tablespoon pure vanilla extract
• 2 cups all-purpose flour (sifted)
• 1 ¾ cups granulated sugar
• ¾ cup special dark cocoa powder
• 2 teaspoons baking soda
• 2 teaspoons baking powder
• 1 teaspoon salt

For the peanut butter buttercream

• 1 cup unsalted butter (room temperature)
• ¾ cup creamy peanut butter (I use Skippy, full-fat recommended)
• 5 cups powdered sugar (sifted)
• 2 teaspoons pure vanilla extract
• ¼ cup heavy whipping cream (or more, as needed)
• ¼ teaspoon salt

For the chocolate ganache:

• 1 cup semisweet chocolate chips (or finely chopped chocolate)
• ½ cup heavy cream

Instructions

For the chocolate cake

• Preheat your oven to 350°F (175°C). Prepare a 9×13 inch metal baking pan by lightly spraying the bottom with non-stick cooking spray, then lining it with a piece of parchment paper cut to fit the bottom. Spray the parchment paper again. If you’re using metal binder clips to hold the parchment paper sides up (which can help for easy removal), ensure they are metal, not plastic. Set the prepared pan aside.
• In a large mixing bowl, sift together the all-purpose flour, granulated sugar, special dark cocoa powder, baking soda, baking powder, and salt. Use a whisk to gently mix these dry ingredients on low speed (or by hand) until they are evenly combined and there are no visible clumps. Set this bowl aside.
• In a separate, smaller bowl, whisk together the room temperature large eggs, room temperature buttermilk, hot water, pure vanilla extract, and vegetable oil. Whisk until all these wet ingredients are thoroughly combined and homogenous.
• Slowly pour the whisked liquid ingredients into the large bowl containing the dry ingredients. Using a whisk, gently mix everything together just until combined. Be careful not to overmix; stop as soon as there are no longer any streaks of dry flour visible. With a rubber spatula, scrape the bottom and sides of the bowl to ensure all the batter is evenly mixed.
• Carefully pour the cake batter into your prepped 9×13 inch cake pan. Use the back of a spoon or an offset spatula to gently spread and even out the batter across the surface of the pan. This ensures uniform thickness, which is key for even baking and a consistent crumb.
• Bake the cake in the preheated oven for 35-40 minutes. To check for doneness, insert a clean toothpick into the center of the cake. It is ready when the toothpick comes out with just a few moist crumbs attached, indicating a perfectly baked and tender cake.
• Once baked, remove the cake from the oven and allow it to cool completely in the cake pan on a wire rack. This is crucial before frosting. While the cake is cooling, you can begin preparing the delicious peanut butter buttercream.

For the peanut butter buttercream

• In the bowl of an electric mixer fitted with the paddle attachment, combine the room temperature unsalted butter and creamy peanut butter. Beat on medium-high speed for approximately 2 minutes, or until the mixture is incredibly smooth, light, and fluffy, with a pale appearance. Scrape down the sides of the bowl as needed.
• With the mixer set to the lowest speed, gradually add the sifted powdered sugar (one cup at a time), vanilla extract, salt, and heavy whipping cream to the bowl. Once all ingredients have been added and are mostly combined (to prevent a sugar cloud), increase the mixer speed to medium. Beat for another 3 minutes, or until the frosting is perfectly smooth, creamy, and wonderfully light. Don’t forget to scrape down the bowl’s sides during this process.
• Optional but recommended: For an even smoother, air-bubble-free frosting, remove the bowl from the mixer and use a sturdy wooden spoon or rubber spatula to vigorously stir the frosting by hand for a minute or two. This helps to release any trapped air bubbles, resulting in a beautifully smooth finish.

For the chocolate ganache

• When the cake is fully cooled and ready for assembly, begin preparing the chocolate ganache. Place the heavy cream in a medium microwave-safe bowl. Heat the cream in the microwave until it is hot and just slightly bubbly around the edges. I recommend starting with 30 seconds, then checking and heating in 15-second intervals as needed, as microwave wattages vary. The goal is hot cream, not boiling. Remove from the microwave, add the chocolate chips (or chopped chocolate) to the hot cream, and let the mixture sit undisturbed for 5 minutes. This allows the heat to melt the chocolate. After 5 minutes, stir gently until the chocolate has completely melted and the mixture is perfectly smooth and glossy.

Assembly

• Once the chocolate cake has completely cooled in the pan, use an offset spatula to spread a generous, even layer of the prepared peanut butter buttercream over the entire top surface of the cake. Ensure it’s spread smoothly and covers all edges. For easier ganache application, place the frosted cake in the refrigerator or freezer for 5-10 minutes to allow the buttercream to set slightly.
• If you haven’t already, prepare your chocolate ganache following the instructions above: heat the cream until hot and slightly bubbly, pour over the chocolate, let sit for 5 minutes, then stir until smooth. Allow the ganache to cool slightly for a few minutes; it should still be pourable but not scalding hot.
• Carefully pour the slightly cooled chocolate ganache over the top of the chilled peanut butter buttercream. Use a clean offset spatula to gently spread the ganache evenly, ensuring it covers the entire surface of the cake. Allow the ganache to set slightly for about 5-10 minutes at room temperature, or a few minutes in the fridge if you’re in a hurry.
• Once the ganache has set a bit but is still slightly tacky to the touch, transfer the remaining peanut butter buttercream to a piping bag fitted with a decorative tip (such as Wilton 8B). Pipe an attractive border around the entire edge of the cake. This adds a beautiful finishing touch and defines the cake’s presentation.
• Optionally, elevate the visual appeal and flavor by garnishing the cake. You can sprinkle it with chopped roasted peanuts, mini chocolate chips, or for the ultimate indulgence, adorn it with chopped Reese’s peanut butter cups.
• Allow the assembled cake to set completely, either at room temperature or in the refrigerator, until the ganache and frosting are firm. This typically takes about 30-60 minutes.
• Once fully set, slice your exquisite Chocolate Peanut Butter Sheet Cake into neat squares or rectangles, and prepare for rave reviews! Enjoy every decadent bite!

Keyword chocolate cake, peanut butter, ganache, sheet cake, easy dessert, crowd pleaser

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