Preheat your oven to 350 degrees Fahrenheit, and spray a 9x13 inch baking dish with nonstick spray. Set aside.
Make the cake, according to box directions.
Allow the cake to cool, and poke with holes, using a large straw, skinny end of a wooden spoon, etc..
In a medium mixing bowl, whisk together the banana pudding mix and milk.
Quickly add 1 cup of the crushed pineapple (with juice) to the pudding and stir to combine.
Quickly pour the pudding mixture into the holes made on the cake. Whatever pudding mixture is left, smooth evenly over top of the cake.
Lightly cover with plastic wrap and move to the refrigerator to chill for 2 hours.
Once cake has chilled, top with the 8 ounces cool whip, smoothing out evenly.
Top with the toasted coconut.
When serving, top each piece with a maraschino cherry or two.