1 pkg. light cake mix
1 pkg. sugar free instant pistachio pudding
1 (8 oz.) carton non-fat vanilla yogurt
3 egg whites
1 tsp. vanilla
1 c. diet lemon lime soda

Combine cake mix, pudding, yogurt, egg whites and vanilla (beat at low speed for a minute). Gradually beat in soda. Pour into a 9 x 13 pan sprayed with non-stick cooking spray.

Bake at 350°F for 30 to 35 minutes or until toothpick comes out clean.

Frosting:

1 1/2 c. cold skim milk
1 pkg. sugar free instant pistachio pudding
2 c. light or fat free whipped topping

Mix the milk and pudding for 2 minutes. Fold in the whipped topping.