Mix and bake cake mix as per package instruction for two round layers. Let layers cool, and then split each layer in half so as to have 4 layers. You can also split in less layers according to your liking.
In a large bowl, whip cream cheese until soft, then gradually mix in confectioners’ sugar (sift the sugar for better results). Stir in the pineapple (without juice) and the drained mandarin oranges, reserving about 5 mandarin orange slices to decorate the top of the cake. Mix in the dry pudding mix. Fold in the whipped topping. If the mixture seems too dry, add in a little pineapple juice.
Place one cake layer on a cake plate, spread with frosting. Place another layer on the first one, and top with more frosting. Repeat until all layers are used, spreading the last bit of frosting on top and sides of the cake, filling any holes. Decorate with reserved mandarin orange slices. Refrigerate for at least 2 hours before serving.
