Neopolitan Layer Cake

Ingredients:
For the chocolate cake:
¾ cup plus 2 tbsp. all-purpose flour
6 tbsp. dark cocoa powder
1 tsp. baking soda
½ tsp. baking powder
½ tsp. salt
1 cup sugar
¼ cup vegetable or canola oil
1 large egg
½ cup black coffee
½ cup buttermilk
1½ tsp. vanilla extract

For the white cake:
2 large egg whites
1¾ cup all-purpose flour
1½ tsp. baking powder
½ tsp. salt
1 cup sugar
8 tbsp. unsalted butter, at room temperature
¾ cup very cold water
½ tsp. vanilla extract
¼ tsp. almond extract

For the strawberry cake:
1¼ cups plus 2 tbsp. all-purpose flour
1¼ tsp. baking powder
¼ tsp. salt
1 cup sugar
1½ oz. strawberry gelatin
8 tbsp. unsalted butter, at room temperature
2 large eggs
½ cup milk
1½ tsp. vanilla extract
¼ cup sweetened strawberry puree*

For the filling:
Easy vanilla buttercream or good quality strawberry jam

For the strawberry buttercream frosting:
1½ cups fresh strawberries (8 oz.), rinsed, hulled and coarsely chopped*
4 large egg whites
1¼ cups sugar
3 sticks (1½ cups) unsalted butter, at room temperature

*To make the strawberry puree, process partially thawed frozen strawberries with a bit of sugar in a blender or food processor until smooth. If using sweetened frozen strawberries, no additional sugar is necessary.

Directions:
To make the chocolate cake, butter and flour the edges of a 9-inch round pan, shaking out the excess flour. Line the bottom with a round of parchment. In a small bowl, combine the flour, cocoa powder, baking soda, baking powder and salt; whisk to blend and set aside. In the bowl of an electric mixer, combine the sugar, vegetable oil and egg. Beat on medium speed until smooth, about 1-2 minutes. With the mixer on low speed, blend in half of the dry ingredients, beating just until incorporated. Blend in the coffee, buttermilk and vanilla just until smooth. Beat in the remaining dry ingredients, mixing just until incorporated.

Preheat the oven to 350˚ F. Pour the batter into the prepared pan and bake, rotating halfway through, until a toothpick inserted in the center comes out clean, about 35 minutes. Transfer to a wire rack and let cool in the pan for 20 minutes. Run a knife around the edges, then turn the cake out onto the rack and let cool completely.

To make the white cake, butter and flour the edges of a 9-inch round pan, shaking out the excess flour. Line the bottom with a round of parchment. In a small bowl, combine the flour, baking powder and salt; whisk to blend and set aside. In the bowl of an electric mixer fitted with the whisk attachment, whip the egg whites on medium speed until foamy. Increase speed to medium high and continue to beat until stiff peaks form. Transfer the egg whites to another bowl and set aside. In the bowl of the electric mixer now fitted with the paddle attachment, combine the sugar and butter, and beat on medium-high speed until light and fluffy, 2-3 minutes. With the mixer on low speed, beat in half of the dry ingredients just until incorporated. Blend in the water, vanilla and almond extracts. Beat in the remaining dry ingredients just until incorporated. With a silicone spatula, stir in about a quarter of the egg whites to lighten the batter. Gently fold in the remaining egg whites, until the batter is smooth and no streaks remain.

Preheat the oven to 350˚ F. Pour the batter into the prepared pan and bake, rotating halfway through, until a toothpick inserted in the center comes out clean, about 35 minutes. Transfer to a wire rack and let cool in the pan for 20 minutes. Run a knife around the edges, then turn the cake out onto the rack and let cool completely.

To make the strawberry cake, butter and flour the edges of a 9-inch round pan, shaking out the excess flour. Line the bottom with a round of parchment. In a small bowl, combine the flour, baking powder and salt; whisk to blend and set aside. Combine the sugar, strawberry gelatin and butter in the bowl of an electric mixer. Beat on medium-high speed until light and fluffy, about 2-3 minutes. Beat the eggs into the sugar mixture one at a time, mixing well after each addition. With the mixer on low speed, add half of the dry ingredients to the batter and mix just until incorporated. Blend in the milk and vanilla extract. Add in the remaining dry ingredients, mixing just until incorporated. Blend in the strawberry puree.

Preheat the oven to 350˚ F. Pour the batter into the prepared pan and bake, rotating halfway through, until a toothpick inserted in the center comes out clean, about 35 minutes. Transfer to a wire rack and let cool in the pan for 20 minutes. Run a knife around the edges, then turn the cake out onto the rack and let cool completely.

To make the frosting, place the strawberries in a food processor or blender. Puree until completely smooth. Combine the egg whites and sugar in a heatproof bowl set over a pot of simmering water. Heat, whisking frequently, until the mixture reaches 160° F and the sugar has dissolved.

Transfer the mixture to the bowl of a stand mixer** fitted with the whisk attachment. Beat on medium-high speed until stiff peaks form and the mixture has cooled to room temperature, about 8 minutes. (The bowl should be cool to the touch.)

Reduce the speed to medium and add the butter, 2 tablespoons at a time, adding more once each addition has been incorporated. If the frosting looks soupy or curdled, continue to beat on medium-high speed until thick and smooth again, about 3-5 minutes more (or longer – don’t worry, it will come together!) Blend in the strawberry puree until smooth and completely incorporated, scraping down the sides of the bowl as needed.

To assemble the cake, torte each of the cake layers horizontally into two thin halves. Place one of the chocolate layers on a cake board or cake platter. Top with a very thin layer of the vanilla buttercream or strawberry jam. Place a layer of the strawberry cake on top. Again, cover with a thin layer of vanilla buttercream or strawberry jam. Top with a layer of the white cake. Cover with a thin layer of the vanilla buttercream or strawberry jam. Repeat the process with the remaining layers of chocolate and strawberry cake. (For a taller cake, you can use the remaining layer of white cake. Otherwise, you can wrap tightly and save for later use or discard.) Frost the top and sides of the cake with the strawberry buttercream. Transfer remaining buttercream to a pastry bag fitted with a decorative tip for detailing as desired.

Source: adapted from the blog, Annie's Eats and Sweetapolita