This pineapple frosting recipe makes enough to fill and top a layer cake. Crushed pineapple gives the frosting its wonderful fruity flavor. It’s a great frosting for cupcakes as well. Only four ingredients go into this simple topping, so it’s as foolproof as it is delicious. For a Bundt or tube cake, halve the recipe but increase the ratio of pineapple and spoon the topping over the cake. Add about 1/2 cup of flaked coconut (toasted, if you like) to the topping for a fun tropical kick.