1 1/2 cup unsalted butter, room temperature
3 cups sugar
3 teaspoons vanilla extract
6 cups all-purpose flour
3 tablespoons + 1 1/2 teaspoon baking powder
1 1/2 teaspoon salt
3 cup milk
2 cups unsalted butter, room temperature
1 teaspoon vanilla extract
5 cups confectioner's sugar
Bake the cakes: Cream the butter and sugar with an electric mixer until pale and fluffy. Add the vanilla extract and eggs and beat until combined. In a separate bowl, combine the flour, baking powder and salt. Add this to the butter mixture in 2 additions, alternating with the buttermilk. Divide the mixture into 4 non-stick cake pans and dye them 4 colors. Bake at 350F for 30-40 minutes, or until fully cooked. Cool for 10 minutes in the pan, then transfer to a wire rack and cool completely. Place the cakes in the freezer until firm (this will make them much easier to slice!).
Make the buttercream: Cream the butter with an electric mixer until pale and fluffy. Add the vanilla extract and beat until combined. Add the confectioner's sugar one cup at a time, then beat for 3-5 minutes, until fluffy.
Assembly: Flatten the cakes and remove the brown sides and bottom. Slice each cake into 4 rings. Swap out the rings between each cake, so that each layer of cake contains one ring of each color. Stack the layers on a cake stand, spreading some buttercream in between each layer. Coat the entire cake in a layer of buttercream and decorate the base of the cake with candies. Slice to reveal the checkerboard pattern inside!