1 (9 inch) prepared chocolate cake mix
1 (3.9 ounce) package instant vanilla pudding mix
1 (8 ounce) container frozen whipped topping, thawed
1/2 cup chopped pecans
Prepare cake mix according to package directions for a 9x13 inch pan.
Preheat oven to 375 degrees F (190 degrees C). Grease and flour a 9x13 inch pan.
In a large bowl, stir together the cake mix, pudding mix and whipped topping. Fold in the pecans. Spread evenly into the prepared pan.
Bake in the preheated oven for 45 minutes, or until a toothpick inserted into the center comes out clean. Allow to cool before serving.