Sugar Free Cake

1 package any cake mix
1 diet soda (coke or pepsi for chocolate, 7up or sprite for lemon, strawberry with strawberry cake mix etc...

1. Place cake mix in mixing bowl
2. Pour in diet soda
3. Stir 1 minute for cake or 2 minutes for moist brownies
4. Bake according to cake mix directions
5. Use sugar free whip cream on top