White Chocolate Peanut Butter Cake
Recipe type: Dessert
Serves: 1 3-layer 8-inch cake
For the White Chocolate Cake:
  • 3 cups all-purpose flour
  • 1 teaspoon baking soda
  • ½ teaspoon fine salt
  • 1 cup (2 sticks, 8 ounces) unsalted butter, room temperature
  • 2 cups granulated sugar
  • 4 ounces white chocolate, melted and cooled
  • 4 large eggs, room temperature
  • 1 tablespoon vanilla extract
  • 1 cup buttermilk, room temperature
  • ½ cup water
  • ½ cup peanut butter chips (optional)
For the Airy Peanut Butter Frosting:
  • 1 ¼ cup (2 ½ sticks, 10 ounces) unsalted butter, room temperature
  • 12 ounces cream cheese, room temperature
  • 2 ½ cups creamy peanut butter
  • 1 tablespoon vanilla extract
  • 6 ¾ cups powdered sugar, sifted
For the Peanut Butter Bomb:
  • 4 ounces cream cheese, room temperature
  • ½ cup creamy peanut butter
  • 1 cup powdered sugar, sifted
  • 2 teaspoons milk
  • 2 teaspoons vanilla extract
  • ⅛ teaspoon salt
  • 2 cups cold heavy cream
For assembly:
  • White chocolate peanut butter cups
  • White chocolate ganache
To make the White Chocolate Cake:
  1. Preheat oven to 350 degrees F. Grease 3 8-inch cake pans with baking spray, set aside.
  2. Whisk the flour, baking soda, and salt in a large bowl. Set aside.
  3. In the bowl of a stand mixer, cream the butter and sugar together until light and fluffy, about 2 to 3 minutes. Scrape down the sides and bottom of the bowl.
  4. Pour in the white chocolate and beat until incorporated. Add the eggs, one at a time, beating well after each addition. Add in the vanilla.
  5. With the mixer on low, add the dry ingredients, alternating with the buttermilk and water, beginning and ending with the dry ingredients. Fold in the peanut butter chips.
  6. Divide the batter between the prepared pans and bake for 25 to 29 minutes, rotating halfway. A toothpick inserted should come out with a few moist crumbs.
  7. Invert immediately onto a wire rack, cool completely before storing or assembly.
To make the Airy Peanut Butter Frosting:
  1. In the bowl of a stand mixer fitted with a paddle attachment, beat the butter on a medium speed until smooth. Add the cream cheese, peanut butter, and vanilla. Beat until smooth and lump free about 1 minute. Raise the speed to medium-high to beat until fluffy, about 2 minutes.
  2. Scrape the sides and bottom of the bowl down.
  3. With the mixer's speed on low, gradually add the powdered sugar. Raise the speed back to medium-high and beat until smooth, about another 2 minutes.
To make the Peanut Butter Mousse:
  1. Line an 8-inch freezer safe bowl with plastic wrap, set aside.
  2. In the bowl of a stand mixer fitted with a paddle attachment beat the cream cheese and peanut butter on a medium speed until smooth and lump free, about 2 minutes.
  3. With the mixer's speed on low, add the powdered sugar followed by the milk, vanilla and salt. Raise the speed to medium-high and beat until smooth. Pour the mixture in a separate bowl.
  4. Clean the bowl of the stand mixer and, using a whisk attachment, whip the heavy cream on a medium speed until medium peaks form.
  5. Use a rubber spatula to fold the whipped cream into the peanut butter mixture. Pour the mixture into the prepared bowl. Press more plastic wrap over the top and chill in the freezer until set. About 4 hours or overnight.
To assemble the White Chocolate Peanut Butter Cake:
  1. If the cake layers have domes, use a serrated knife to level off the tops. Spread a bit of frosting onto the cake board and secure the first cake layer.
  2. Use a pastry bag to pipe on a thin even layer of peanut butter frosting. Place white chocolate peanut butter cups evenly onto the frosting. Pipe more frosting on top pf the candies. Repeat this step with the second cake layer and top with the final third layer.
  3. Apply a thin crumb coat to the outside of the cake and place in the freezer to firm up, about 20 to 25 minutes. Cover the cake with a thicker application of frosting and rest in the refrigerator for 10 minutes. Drip chocolate ganache over the sides of the cake. Refrigerate again.
  4. Remove the Peanut Butter Mousse Bomb from the freezer. Place on top of the chilled cake. Top with white chocolate ganache and peanut butter cup pieces. Use the remaining frosting to pipe a boarder.
  5. If you aren't eating the cake all in one sitting, store the mousse in the freezer and the cake in the fridge.
Cake recipe adapted from Layered, Frosting recipe from Wicked Good Kitchen
Recipe by Layer Cake Parade at http://layercakeparade.com/white-chocolate-peanut-butter-cake/