American Flag Cake

3 (10.25 ounce) packages white cake mix

9 egg whites

1 cup vegetable oil

3 3/4 cups whole milk

2 tablespoons clear vanilla extract

2 tablespoons red food coloring

1 tablespoon blue food coloring

1 cup white chocolate chips

10 cups fluffy white frosting

1 tablespoon white chocolate chips, or as needed

2 tablespoons white sugar, or as needed

1 4-inch round paper or cardboard stencil

What You Need