Preheat oven to 350°F. Combine cake mix, oil, buttermilk, flour, and vanilla until well mixed. Add egg whites and mix until combined. Pour batter into a Sweet Creations Textured Nonstick 12 Cup Muffin/Cupcake Pan and bake for 15-20 minutes.
Place butter in a medium bowl with electric mixer and beat until creamy. Beat in vanilla. Sprinkle in powdered sugar, 1 cup at a time, beating well between additions and scraping the side of the bowl often. Add milk, one teaspoon at a time, until a soft, thick glaze consistency is reached. Squirt a small amount of gel food coloring in an Oodle Tips icing bag and rub around to coat bag. Place frosting into bag, and pipe onto cupcakes to create a two-toned frosting look.