Mix sweetened condensed milk and coco lopez together and place in refridgerator. Prepare Cake as stated on box but add 1 tsp of rum extrac and bake at 350 for 35-40 min. Take toothpick and check to make sure that cake is done. Take a lg hole straw (sonic straw or jack in box straw) and randomly punch holes in cake poor mixture over top of cake while still warm and place in refridgerator. After 1hr put Cool Whip on top of cake for icing. This is a Very moist Sweet cake if you don't put Cool whip ontop. Enjoy!!