Chocolate Peanut Butter Cake

Chocolate peanut butter cake is perfect for Reese’s lovers! Moist dark chocolate cake, creamy peanut butter frosting, chocolate ganache drip, and Reese’s peanut butter cups make this decadent and delicious dessert.

Ingredients for Chocolate Peanut Butter Cake

Chocolate cake

• All-purpose flour
• Granulated sugar
• Dark cocoa powder: Use dark cocoa powder for the best chocolate flavor. My favorite is Hershey’s Special Dark Cocoa Powder which is a dutch-processed cocoa powder.
• Baking soda: A leavening agent to help the cake rise.
• Baking powder: Another leavening agent to help the cake layers rise.
• Salt: Salt enhances the flavor of the chocolate in the cake. 
• Milk: Room temperature milk. You can also use buttermilk.
• Eggs: Large eggs, room temperature.
• Vegetable oil: Or your preferred neutral baking oil.
• Vanilla extract: Pure vanilla extract enhances the flavor of the chocolate.
• Boiling water: Boiling water helps bring the batter together.
• Espresso powder: Espresso powder makes the chocolate taste more chocolatey.

Peanut butter buttercream frosting

• Unsalted butter: Room temperature, softened butter.
• Peanut butter: Regular, creamy peanut butter.
• Powdered sugar: Confectioners’ sugar and icing sugar.
• Vanilla extract: Pure vanilla extract adds great flavor to the buttercream. 
• Salt: A pinch of salt adds some contrast to the sweetness of the buttercream. 
• Heavy cream: Heavy cream or heavy whipping cream makes the buttercream smooth and creamy.

Additional components

• Semisweet chocolate chips + heavy cream = chocolate ganache drip.
• Reese’s peanut butter cups: For filling and decoration.

How to Make the Components for Chocolate Peanut Butter Cake

Chocolate cake

1. Preheat oven to 350 degrees F and prepare three 7-inch cake pans with nonstick cooking spray and parchment paper circles.
2. In a large bowl, whisk together the dry ingredients (all-purpose flour, granulated sugar, dark cocoa powder, baking soda, baking powder, and salt).
3. Add in eggs, milk, vegetable oil, and vanilla extract. Whisk to combine.
4. Combine boiling water and espresso powder. Add this mixture to the cake batter.
5. Gently stir the cake batter until combined and smooth.
6. Pour the batter into the prepared pans. Use a kitchen scale to weigh the batter for even layers.
7. Bake the cake layers for approximately 30 minutes.
8. Cool the cakes in the pan for 15 minutes before removing and transferring to a wire rack to cool completely.

Peanut butter buttercream frosting

To make the peanut butter buttercream frosting, you will need a stand mixer or an electric hand mixer. If you are using a stand mixer, you can use either the paddle attachment or the whisk attachment – whatever your preference is!

1. Whip the room temperature butter for about 5 minutes until light, fluffy, and pale in color.
2. Add in peanut butter and mix until well combined.
3. Add in half of the powdered sugar and mix on the lowest speed until the sugar is combined with the butter. Then add the remaining half of the powdered sugar and continue to mix on low speed.
4. Add the vanilla extract and salt and continue to mix on low until combined.
5. Slowly drizzle in the heavy cream. Be sure to scrape the sides and bottom of the bowl after this step to ensure everything is well mixed.
6. Turn the mixer to medium speed and whip the buttercream for about 3 minutes.

Chocolate ganache

You can make the chocolate ganache in the microwave or stovetop version! Basically, melt the chocolate with hot heavy cream and stir to create a smooth, shiny ganache.

Assembling the Chocolate Peanut Butter Cake

1. Level the cake layers with a serrated knife.
2. Place one chocolate cake layer on a round cake board. Add desired amount of frosting to the top of the layer and spread evenly with an offset spatula.
3. Sprinkle on half of the chopped Reese’s peanut butter cups. Add a bit more frosting and spread evenly with an offset spatula to lock in the chopped peanut butter cups.
4. Add the second cake layer, more peanut butter frosting, remaining chopped peanut butter cups, and spread evenly with an offset spatula.
5. Add the final cake layer to the top of the cake. Be sure the bottom of the cake layer is facing up.
6. With an offset spatula, add a crumb coat, a thin layer of frosting, to the top and sides of the cake. Use a cake scraper to remove excess buttercream and to smooth the sides. Chill the cake for 20 minutes to firm the buttercream.
7. Add a generous layer of frosting to the chilled cake with an offset spatula. Use a cake scraper to remove excess frosting and smooth the sides of the cake. Chill for an additional 20 minutes.
8. Use a piping bag or squeeze bottle to add a chocolate ganache drip around the sides of the cake.
9. Use a piping bag fitted with a Wilton 1M piping tip to create swirls of peanut butter buttercream around the top edges of the cake with additional peanut butter cups.

Check out my baking tutorial blog post on how to frost a layer cake to learn all of the steps involved in filling, stacking, and frosting a basic layer cake to learn more!