Beat the cake mix, water, vegetable oil, and egg whites together on low speed for 30 seconds, then on medium for 2 minutes, until smooth. Fill cupcake liners 1/3 full with white batter; set aside.
Mix more food coloring into the remaining bowl of pink batter until it is an orange/red color and pour the batter into a resealable plastic bag. Cut a corner off the bag, stick the open tip into the center of each cup of white batter and squeeze in about two tablespoons of red batter.
Bake the layered cupcakes in the preheated oven until a toothpick inserted into the center comes out clean, 15 to 20 minutes. Cool completely before frosting.