Drain pineapple juice in a medium sized bowl. Mix in the Jell-O Vanilla Instant Pudding mix, and then mix in 1 cup of the Cool Whip. Now fold in the crushed pineapple.
Split angel food cake crosswise. Spread the bottom layer with half the pineapple-pudding mix. Put on the top of the cake. Frost the sides with the remaining Cool Whip.
Use the remainder of the pineapple-pudding mix to spread on top of the cake. Now, sprinkle the top of the cake with toasted coconut and decorate with the drained mandarin oranges. Refrigerate until ready to serve.