Prepare and bake the cake according to the directions on the box for a 9x13-inch pan. Make sure to grease your dish before adding the cake batter. My cake baked at 350˚F for 34 minutes. Allow cake to cool to room temperature.
Meanwhile, toast the coconut on an un-greased baking sheet at 350˚F for 3 minutes. Stir it up, and then continue baking and stirring every 30 seconds to 1 minute or until golden brown. Coconut browns and burns quickly, so stay right by the oven and stir it frequently. Allow the toasted coconut to cool.
Using a fork or wooden spoon, poke holes all over the top of the cooled cake. Open the can of Cream of Coconut, empty it into a 2-cup measuring glass and heat it for 15 seconds in the microwave. Whisk the mixture well and then pour it all over the cake and into the holes. Allow the cake to soak up all of the Cream of Coconut, about 5 to 10 minutes.
Frost the cake with cool whip and sprinkle the top with the toasted coconut. Cut and serve immediately. Keep leftovers refrigerated.
Notes
This cake can be prepared ahead of time and be stored in the refrigerator, just wait to put the toasted coconut on top until just before serving it, if you want the coconut to stay crispy and not go soft.