1Make cake mix as directed on box except that in the place of water put pineapple juice. Bake according to the cake mix directions and take right from oven and place in freezer. Cake is ready to frost when cool on the bottom to touch.
2Mix crushed pineapple, instant pistachio pudding, and whipped topping together with a spoon, do not use an electric mixer. Frost cake and refrigerate for at least one hour. You must keep this cake refrigerated until ready to serve and then also keep any leftovers refrigerated.