Preheat the oven to 350℉ degrees and grease a 9x13 inch cake pan

In a large bowl or stand mixer on low speed mix the cake mix, eggs, water, coconut rum and butter together until incorporated. Increase the speed to medium and continue to mix for two minutes

Stir in the pineapple and pour into baking dish

Cook for 25 minutes or until lightly browned and toothpick inserted into center comes out clean

During the last 5 minutes of baking, whisk together the cream of coconut, pineapple rum and milk

As soon as the cake comes out of the oven poke the cake all over with a fork and then pour the mixture all over the top

Cool in the pan completely; after about 10 minutes, put it in the refrigerator to get a good chill

Once the cake is completely cooled, whip the heavy cream and sugar in a large mixing bowl or stand mixer on high speed, beat until soft peaks form

Spread or pipe the cream on top of the chilled cake

To toast the coconut, place a thin layer on a paper plate and microwave on high at 15 second intervals, stirring between each, until light golden brown and fragrant

Garnish with coconut flakes and refrigerate