Begin by preheating the oven to the degrees listed on cake mix box. Prep two muffin tins by lining with cupcake wrappers.
In a large bowl combine the cake mix, egg whites called for on cake mix, oil called for on cake mix and replace the water with the same amount of champagne. Mix on medium speed for 2 minutes.
Fill the cupcakes 3/4 of the way full and bake for instructed time on cake mix box.
Let the cupcakes cool completely before frosting.
Beat the butter with a hand mixer until it is light and fluffy. Slowly add in the powdered sugar and mix until well combined.
Add in 2 tablespoons of champagne and mix well, continue adding the champagne 1 tablespoon at a time until the desired consistency has been reached for the frosting.
Decorate with sprinkles.