To make cake batter, you need quite a few ingredients. These include flour, sugar, baking powder, salt, eggs, coconut cream, vanilla, coconut extract, rum extract or rum, butter, crushed pineapple, and sweetened flaked coconut. Some of these ingredients are repeated in the frosting, but you’ll want additional items like cream cheese, powdered sugar, and heavy cream.
I don’t feel the need to buy an expensive bottle when using rum for both the dough and frosting. A small one works well, and as Case assures, “Any kind of rum works well for this recipe.”