1. Mix and bake the yellow cake according to package instructions. Let it cool to room temperature.
2. Leaving the cake in its glass bake pan, cover and refrigerate it until it is needed.
3. Open the pineapple and mandarin oranges and let them set in strainers for 1/2 hour, then refrigerate until needed.
4. Mix the pineapple and mandarin orange juices together and refrigerate until needed.
5. When the cake is totally cooled, remove it from the refrigerator.
6. With a small fork make a pattern of holes in the top of the cake and pour the juice from the pineapple and the mandarin oranges over the cake, but do not waterlog the yellow cake. Do not use all of this juice mixture.
7. Remove the strained mandarin oranges from the refrigerator and line them up on a paper towel, choosing only those that are fully formed. Arrange the oranges in a pattern of 3 rows within the dimensions of the 9 x 13” cake pan to determine if there are enough fully formed orange sections to use on the cake top to form butterflies. Put aside until the cake is fully assembled.
8. Remove the drained pineapple from the refrigerator and layer it on the cake top. Small damaged pieces of mandarin oranges may also be added to this layer.
9. Return the cake with the fruit layer to the refrigerator until the cream topping is made.
10. In the small mixing bowl, beat the cream cheese and the powdered sugar until it is creamy: 60 to 90 seconds. It helps to bring the cream cheese to room temperature before mixing with the powdered sugar.
11. In the large mixing bowl, mix 1 small instant pudding with 1 cup of milk for 60 seconds.
12. Add the cream cheese and the cool whip to the pudding in the large bowl and mix all ingredients to a smooth creamy texture.
13. Remove the cake from the refrigerator and cover the entire cake and fill the crevice between the yellow cake and the glass cake pan with the mixture of cream cheese, cool whip, and pudding.
14. Before the pudding sets in the cream topping, arrange the mandarin oranges on the top in the shape of butterflies in a pattern that would allow a mandarin orange butterfly on each cut of cake. If the mandarin oranges are not fully formed, a third can may have to be opened to provide a sufficient number of orange pieces to form the butterflies.
15. Cover the finished dessert and cool before serving. Very refreshing after a heavy cookout!