1 (18 ounce) package yellow cake mix
1 (3 ounce) package instant vanilla pudding mix
1 (3 ounce) package instant chocolate pudding mix
2 1/2 cups white sugar
1/2 cup vegetable oil
1 1/2 cups milk
2 eggs, beaten
1 teaspoon vanilla extract
1 (8 ounce) container sour cream
1 teaspoon vanilla extract
1/2 cup butter, softened
1 teaspoon instant vanilla extract
2 cups confectioners' sugar for dusting
Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch pan.
In a large bowl, mix the cake mix, pudding mix, pudding mix, sugar, vegetable oil and milk. Stir the flour mixture into the milk mixture just until incorporated. Pour batter into prepared pan.
Bake in the preheated oven for 45 minutes, or until a toothpick inserted into the center of the cake comes out clean. Cool completely before frosting. Dust with confectioners' sugar before frosting. Allow to cool completely before cutting into squares.