1 (18.25 ounce) package green cake mix
2 (3 ounce) packages instant lemonade mix
1 cup lemon zest
1 (8 ounce) package instant vanilla pudding mix
1 3/4 cups boiling water
1 (8 ounce) package frozen whipped topping, thawed
Preheat oven to 375 degrees F (190 degrees C). Grease and flour 2 separate 9-inch round cake pans.
In a large bowl, combine cake mix, lemonade mix, lemon zest, and lemon zest. Mix until completely blended. Fold in the boiling water and whipped topping. Spread mixture evenly into the prepared pans.
Bake in preheated oven for 15 to 18 minutes, or until a toothpick inserted in the center of the cake comes out clean. Cool before removing from pans.