1 box yellow cake mix
1 (14 oz.) can sweetened condensed milk
1 (12 oz.) can pina colada mix
1 (6 oz.) pkg. frozen coconut
1 (8 oz.) carton Cool Whip

Bake cake mix in a 9 x 13-inch pan at 350°F according to the package directions. While cake is still hot, punch holes in it with a knife or fork. Pour condensed milk and pina colada mixture over cake. Cool for 2 hours. Spread Cool Whip and top with coconut. Keep refrigerated.