Cake: 3 cups flour; 2 cups sugar; 1/4 tsp. sea salt; 3 tsp. baking powder; 5 egg whites; 1 and 1/2 cups water; 1 cup vegetable oil; 1 tsp. vanilla; 1 tsp. Wilton butter flavoring
Icing: 1 pint heavy whipping cream; 1 cup powdered sugar; 1/4 tsp. vanilla; 1/4 tsp. Wilton butter flavoring
Cake: Preheat oven to 350 degrees. Grease 2 8x8 cake pans. Set aside. In a large mixing bowl, combine the flour, sugar, salt, and baking powder. Stir. In another large mixing bowl, combine the egg whites, water, oil, vanilla, and butter flavoring. Stir to combine. Add the wet ingredients to the dry ingredients. Using a hand mixer, mix batter on medium speed for 2 minutes. Divide batter equally among the 2 cake pans.
Icing: Pour the heavy whipping cream into the chilled bowl. Beat on medium high speed until stiff peaks form. Add the powdered sugar, vanilla extract, and butter flavoring. Stir for 30 additional seconds, or until combined. When cake is cooled, level cakes with a serrated knife. Place one cake layer on a serving platter. Use half the icing to frost sides and top of cake layer. Place the remaining layer on top. Frost top and sides of top layer.