Preheat oven to 350ºF.
Prepare three 8-inch round cake pans by spraying them with non-stick cooking spray and dusting with a thin layer of flour.
In a large mixing bowl, cream the sugar and butter together for 2 minutes or until light and fluffy.
In another bowl, mix flour, baking powder, and salt together.
In a separate bowl, beat the egg whites, milk, and vanilla together until combined.
Add ⅓ of the flour mixture to the butter mixture. Beat well.
Add ⅓ of the egg mixture to the butter mixture. Beat well.
Continue alternating until all ingredients are combined and mixed well.
Divide the batter evenly between the three prepared cake pans.
Bake for 18 minutes or until a toothpick comes out clean. OR when they spring back when gently pressed in the center.
Allow the cakes to cool for 15 minutes before flipping them onto a cooling rack. You may need to use a knife or spatula to loosen them a bit around the edges.
Allow them to cool completely before decorating.
Prepare the frosting by placing the heavy whipping cream in a medium mixing bowl.
With a hand or stand mixer, beat the heavy cream for 3-5 minutes or until peaks begin to form.
Add the confectioner's sugar and vanilla. Beat until the frosting is whipped and spreadable.
Assemble the cake by alternating the cake layers and the frosting layers.
Decorate with flowers of your choice and serve.