The Whiteout Cake Ingredients For the white cake layers 2 1/2 cups of cake flour 3/4 cup all-purpose flour 1 tablespoon baking powder 1 teaspoon baking soda 3/4 teaspoon salt 1/2 cup (1 stick) unsalted butter, softened 1/2 cup vegetable shortening 1 3/4 cups sugar 1 tablespoon pure vanilla extract 1 large egg 1