Preheat oven to 350 degrees
In a medium sized bowl, whisk the all purpose flour, baking soda, baking powder, salt, and set aside.
In a large bowl beat the butter and sugar until nice and fluffy
Add the vanilla extract and egg whites to the sugar mixture and mix until well incorporated
Add the flour mixture to the butter and sugar mixture alternating with the milk
Fold in the sprinkles
Pour the batter into three greased 8 inch baking pans and bake for 25 minutes or until done
To make the frosting, mix the unsalted butter for about 2 minutes
Add the powdered sugar, milk, and vanilla extract, mix for about 3 minutes on high speed.