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Peanut Butter Cup Cake: The Ultimate Recipe and Baking Guide


  • Total Time: 120 minutes
  • Yield: 10-12 servings 1x

Description

Decadent chocolate cake layered with creamy peanut butter filling and topped with a rich chocolate ganache. A peanut butter cup lover’s dream!


Ingredients

Scale
  • 2 cups all-purpose flour
  • 2 cups granulated sugar
  • ¾ cup unsweetened cocoa powder
  • 1 ½ teaspoons baking powder
  • 1 ½ teaspoons baking soda
  • 1 teaspoon salt
  • 1 cup buttermilk
  • ½ cup vegetable oil
  • 2 large eggs
  • 2 teaspoons vanilla extract
  • 1 cup boiling water
  • 1 cup (2 sticks) unsalted butter, softened
  • 3 cups powdered sugar
  • 1 cup creamy peanut butter
  • ¼ cup heavy cream
  • 1 teaspoon vanilla extract
  • Pinch of salt
  • 1 cup heavy cream
  • 12 ounces semi-sweet chocolate chips
  • 2 tablespoons unsalted butter
  • Mini peanut butter cups, halved
  • Chopped peanuts

Instructions

  1. Preheat oven to 350°F (175°C). Grease and flour two 9-inch round cake pans (or use baking spray with flour). Line the bottoms with parchment paper rounds.
  2. In a large bowl, whisk together the flour, sugar, cocoa powder, baking powder, baking soda, and salt.
  3. In a separate bowl, whisk together the buttermilk, oil, eggs, and vanilla extract.
  4. Gradually add the wet ingredients to the dry ingredients, mixing on low speed until just combined. Do not overmix.
  5. Slowly pour in the boiling water while mixing on low speed. The batter will be thin.
  6. Divide the batter evenly between the prepared cake pans. Bake for 30-35 minutes, or until a wooden skewer inserted into the center comes out clean.
  7. Let the cakes cool in the pans for 10 minutes before inverting them onto a wire rack to cool completely.
  8. In a large bowl (or stand mixer), beat the softened butter until light and fluffy (2-3 minutes).
  9. Gradually add the powdered sugar, one cup at a time, beating on low speed until combined.
  10. Add the peanut butter and beat until well combined. Scrape down the sides of the bowl as needed.
  11. Pour in the heavy cream and vanilla extract. Beat on medium speed until smooth and creamy. Add a pinch of salt.
  12. If the frosting is too thick, add more heavy cream (1 tablespoon at a time). If it’s too thin, add more powdered sugar.
  13. In a saucepan, heat the heavy cream over medium heat until it just begins to simmer. Do not boil.
  14. Remove from heat and pour the hot cream over the chocolate chips in a heatproof bowl.
  15. Let the mixture sit for 1-2 minutes.
  16. Gently stir until the chocolate is completely melted and the ganache is smooth and glossy.
  17. Stir in the butter until melted and incorporated.
  18. Let the ganache cool slightly before pouring it over the cake.
  19. If necessary, level the cakes with a serrated knife.
  20. Place one cake layer on a serving plate or cake stand.
  21. Spread an even layer of peanut butter filling over the first layer.
  22. Carefully place the second cake layer on top of the filling.
  23. Pour the slightly cooled ganache over the top of the cake, allowing it to drip down the sides. Use an offset spatula to spread evenly.
  24. While the ganache is still wet, decorate with halved mini peanut butter cups and chopped peanuts.
  25. Refrigerate for at least 30 minutes to allow the ganache to set.
  26. Remove from the refrigerator 15-20 minutes before serving. Slice and enjoy!

Notes

  • For best results, use high-quality cocoa powder and chocolate chips.
  • Be careful not to overmix the cake batter, as this can result in a tough cake.
  • The boiling water in the cake batter helps to bloom the cocoa powder and creates a super moist cake.
  • Adjust the consistency of the peanut butter filling to your liking by adding more heavy cream or powdered sugar.
  • Let the ganache cool slightly before pouring it over the cake to prevent it from running off the sides completely.
  • Chilling the cake before serving helps the flavors meld together and makes it easier to slice.
  • Prep Time: 45 minutes
  • Cook Time: 30 minutes