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two layer chocolate banana cake with peanut butter frosting. slice of cake on a pale gray plate sitting on a contrasting gray fringed charger. background is gray abstract and there is a black candle in the back left corner.

Chocolate Banana Cake

Heather Wolf
This Chocolate Banana Cake with Peanut Butter Frosting is flavorful and amazingly moist thanks to the magic of mashed bananas, sour cream and buttermilk.
5 from 9 votes
Prep Time 30 minutes
Cook Time 40 minutes
Total Time 1 hour 10 minutes
Course Cakes and Cupcakes
Cuisine American
Servings 8

Ingredients
  

Chocolate Banana Cake

  • 2 1/4 cups all-purpose flour unbleached
  • 3/4 cup unsweetened cocoa powder
  • 2 tsp baking soda
  • 1 tsp baking powder
  • 1/2 tsp sea salt fine
  • 1 tsp espresso powder (optional)
  • 1 cup unsalted butter softened to room temperature
  • 2 cups granulated sugar
  • 3 large eggs room temperature
  • 2 cups overripe bananas, mashed (approximately 4 large bananas)
  • 1 cup full fat sour cream room temperature
  • 2 tsp vanilla extract pure
  • 1/2 cup buttermilk room temperature
  • 1 cup mini chocolate chips
  • 1 tbsp all-purpose flour unbleached

Peanut Butter Frosting

  • 1/2 cup unsalted butter softened to room temperature
  • 1 cups creamy peanut butter
  • 2 cups powdered sugar
  • 3 tbsp heavy cream room temperature

Instructions
 

Chocolate Cake

  • Preheat oven to 350 degrees.
  • Grease bottoms and sides of two 9-inch round, high-sided baking pans. Place parchment paper rounds into bottom of pans then grease the parchment paper. Set aside.
  • In a large mixing bowl, sift together dry ingredients: flour, cocoa powder, baking soda, baking powder, salt and espresso powder. Set aside.
  • In a separate bowl, use an electric mixer to beat butter and sugar until creamy smooth – approximately 3 minutes.
  • Add eggs, one at a time, beating after each addition until incorporated. Scrape down the sides of the bowl with a spatula as needed.
  • Beat in mashed bananas, sour cream and vanilla.
  • Reduce mixer speed to low. Alternate between adding 1/4 cup of buttermilk and half of flour mixture in 2 separate batches, beating after each addition until just barely combined. Avoid overmixing.
  • Coat mini chocolate chips with 1 tablespoon of flour then gently stir them into the cake batter with a spoon until evenly distributed.
  • Evenly divide batter between the 2 baking pans, smooth the tops with a spatula then bake for 40 to 45 minutes or until a tester inserted into the center of cake comes out clean.
  • Remove baking pans from oven then place on a wire rack to cool completely, approximately 2 hours, before frosting.

Peanut Butter Frosting

  • Beat butter and peanut butter with an electric mixer until creamy and smooth.
  • Reduce mixer speed to low, add powdered sugar and heavy cream. Beat for 1 minute then increase mixer speed and beat until fluffy.
    Note: If frosting is too thick, add more cream in 1 tablespoon increments until desired consistency is reached.

Assembly

  • After cakes have cooled completely, turn them out from their pans then level tops with a cake leveler or serrated knife.
  • Using an offset spatula, frost the top of both cakes with an equal amount of buttercream then gently stack one cake layer on top of the other.
    *If you'd like to frost the sides of the cake, double the peanut butter frosting recipe.

Store

  • Cover and store frosted cake in the refrigerator up to 5 days.
Keyword banana, cake, chocolate, frosting, peanut butter