Diet Coke Cake

I've heard of using this before but I had never tried it. I decided to use my friends Megan, Windi and Marie my guinea pigs to try this recipe out and they approved! 

1 box chocolate cake mix (but can use any flavor)

1 can diet coke

2 egg whites

Mix together, bake according to cake directions! I made cupcakes out of the them. Yummy alone or top with light cool whip!