Step 1

Mix the first four ingredients in a large bowl.

Step 2

Pour cake batter into a 12x18 pan. Bake at 325 degrees for 15 minutes. Let cake cool before adding frosting.

Step 3

In a mixer, or with a blender, beat pudding mix, crushed pineapple, and whipped topping together.

Step 4

Spread frosting generously over the cooled cake. The frosted cake should be kept in the refrigerator until it is served.

Step 5

Top with sliced mandarin oranges right before serving.