Watergate Cake    

Ingredients
1 (18.25-ounce) package white cake mix
1 (3.5-ounce) package instant pistachio pudding mix
3 large eggs
1 cup vegetable oil
1/2 cup chopped walnuts
1 cup club soda

Directions:
Preheat oven to temperature suggested on cake mix box.
Blend together cake mix and instant pistachio pudding mix. Add eggs, cooking oil, chopped walnuts, and club soda. Mix until blended, then beat for 4 minutes at medium speed.
Pour the batter into the greased and floured 9 x 9-inch square pan and bake for 45 to 50 minutes. Cool for 20 minutes then turn out onto a serving plate.
Makes 12 servings.