Preheat oven to 350 degrees F (175 degrees C). Grease a 9x13 inch baking dish.
Combine cake mix, pudding mix, pineapple, and mandarin oranges in a large bowl. Pour into prepared baking dish. Bake in preheated oven for 40 minutes, or until a toothpick inserted into the center comes out clean.
Cool the cake completely before spreading the Cool Whip over the top. Sprinkle with pecans.
Interesting Facts
This cake is often served in a punch bowl.
This cake can be made with different flavors of cake mix and pudding.
This cake can be served with different fruits, such as blueberries, strawberries, or raspberries.