This rum-infused pineapple upside-down cake recipe is perfect for adults who enjoy a little bit of alcohol in their desserts. The cake batter is made with flour, sugar, baking powder, salt, butter, eggs, milk, and rum in the food processor. The pineapple topping is made the same way as the classic recipe. The cake is baked until golden brown and served warm. It's a delicious and boozy dessert that's perfect for special occasions.