Go Back
+ servings

Chocolate-Peanut Butter Fun Cake

Chocolate Peanut Butter Fun Cake is purely magical for lovers of chocolate and peanut butter. A moist and delicious chocolate cake is topped with a buttery and luscious peanut butter frosting.
Course Dessert
Cuisine American
Prep Time 20 minutes
Cook Time 40 minutes
Total Time 1 hour
Servings 12
Calories 334kcal
Author Christin Mahrlig


Cake Batter

  • 1 1/4 cups all-purpose flour
  • 1 cup sugar
  • 3/4 cup unsweetened cocoa powder
  • 1 1/2 teaspoons kosher salt or 1 teaspoon table salt
  • 1 teaspoon baking soda
  • 1/4 cup vegetable oil
  • 1 teaspoon vanilla extract
  • 1/2 cup finely chopped semi-sweet chocolate (3 1/2 ounces)

Peanut Butter Frosting

  • 1/2 cup sugar
  • 1/4 cup egg whites (2 large egg whites)
  • 1 1/2 teaspoons vanilla extract
  • 1/3 cup peanut butter
  • 6 tablespoons unsalted butter cut into 1/4-inch cubes, chilled
  • pinch of salt
  • 1/4 cup finely chopped semi-sweet chocolate
  • 1/4 cup chopped dry-roasted peanuts


  • Preheat oven to 350 degrees. Coat an 8-inch square pan with cooking spray. Line bottom with parchment paper.
  • In a large bowl, whisk together flour, sugar, cocoa powder, salt, and baking soda.
  • Add oil, vanilla extract and 1 1/4 cups water and stir until smooth. Fold in 1/2 cup chopped chocolate.
  • Pour into prepared pan and bake for 35-40 minutes. Cool completely in pan.
  • To make frosting, combine sugar and egg whites in a medium metal bowl set over a saucepan of simmering water. Continuously whisk until sugar dissolves and mixture is hot to the touch, about 3 to 4 minutes.
  • Transfer mixture to the bowl of an electric stand mixer and beat with whisk attachment until cool and thick, about 5-6 minutes.
  • Beat in vanilla extract and then peanut butter.
  • With mixer on medium-high, add butter pieces a few at a time. Beat until butter is completely incorporated. Add a pinch of salt.
  • Run a knife around edges of cake and turn it out onto a plate or cake stand. Peel parchment paper off and top with frosting, chopped chocolate, and peanuts.


Store airtight at room temperature.


Calories: 334kcal