1Bake cake as directed on box for a 9 x 13 inch cake.
2As soon as it comes out of the oven, punch holes all over the top of the cake with a meat fork (try not to hit bottom, but if you do, it's alright). Mix condensed milk and Pina Colada mix together and pour over cake.
3Chill overnight.
4Before serving, frost with whipped dessert topping (Cool Whip (TM) ) and sprinkle with coconut.