Drain both cans of MANDARIN ORANGES (Keep separate). Drain the CRUSHED PINEAPPLE (reserve the juice, you will use it in the cake mx). Grease and lightly flour 13X9 cake pan. PreHeat oven @ 350 degrees.
Mix cake according to pkg. directions - however, use the reserved pineapple juice as part of the water recipe calls for. Fold in the crushed pineapple. Bake according to directions. Please note, cake usually bakes a bit longer, due to the pineapple in it.
When cake is done, remove from oven... poke small holes in top (all over). Mix jello according to directions, however emit 1/2 cup of water called for. Drizzle jello over cake and refrigerate uncovered over night.
Top cake with Cool Whip and decorate with Mandarain Oranges - ENJOY. Cake is DELICIOUS AND REFRESHING IN THE SUMMERTIME.