1-First step: prep the pan and oven Preheat your oven to 350°F. Coat a bundt pan generously with butter and flour so the cake will release easily later. This matters a lot with any pineapple upside down cake because the sugar topping can stick if the pan is not well prepared. If you are using a dark or non-stick pan, you can lower the oven temperature to 325°F. That helps keep the edges from browning too fast.

2-Second step: build the topping Pour the first 1/4 cup of melted butter into the bundt pan. Sprinkle the 1 cup of packed light brown sugar evenly over the butter. This layer melts into a glossy caramel base while the cake bakes. Next, arrange the halved pineapple slices along the ridges of the pan. Place the maraschino cherries in between the fruit pieces. Try to keep the design neat, since this will be the top of the cake after flipping.

3-Third step: mix the batter In a large bowl, combine the yellow cake mix, 3 eggs, the second 1/4 cup of melted butter, reserved pineapple juice mixed with enough water to total 1 cup, and the optional vanilla extract. If your cake mix box calls for oil, leave it out and use the melted butter instead. That swap gives the bundt cake better flavor and a softer texture.

4-Fourth step: pour and bake Carefully pour the batter into the pan over the fruit layer. Do not stir or move the pineapple and cherries around. Smooth the top gently so the batter is even. Bake for 30 to 35 minutes, or until a toothpick inserted in the center comes out clean. Try not to open the oven while it is baking. Letting heat out too early can make the cake sink.

5-Final step: flip, cool, and serve Once the cake is done, invert the pan onto a serving plate. Leave the pan in place for about 5 minutes so the topping can settle. Then carefully lift the pan away. Let the cake cool for another 25 minutes before serving. That short rest helps the caramel topping set and makes slicing easier. The total recipe time is about 1 hour 10 minutes, with 10 minutes of prep, 30 minutes of cooking, and 30 minutes of cooling.