My friend, Briana, taunts me with photos of amazing cupcakes and frosting concoctions that make my mouth water. I've eaten them and cake boss Duff has some serious competition. This Margarita Frosting is amazing and complements this Margarita cupcakes recipe. Margarita Frosting Recipe Type: Frosting Author: Briana Ingredients 1 1/2 cups butter (3 sticks) 4 cups