Creating this Caramelized Pineapple Upside-Down Cake is a rewarding process, broken down into simple, manageable steps. Follow these instructions carefully to ensure a perfectly baked and beautifully caramelized dessert:

Step 1: Prepare the Caramel and Pineapple Topping

1. Melt the Butter: In a 9×13 inch baking pan (or a 10-inch cast iron skillet for a rustic presentation), melt ½ cup (1 stick) of unsalted butter over medium heat on the stovetop. If using the oven, you can melt the butter directly in the pan while the oven preheats, but watch it closely to prevent burning.
2. Add Brown Sugar: Once the butter is melted, remove the pan from the heat (or turn off the stovetop burner if using the oven method). Sprinkle 1 cup of packed light brown sugar evenly over the melted butter. Do not stir.
3. Arrange Pineapple Rings: Carefully arrange the pineapple rings in a single layer over the brown sugar mixture. You can overlap them slightly if needed to fit them snugly in the pan.
4. Add Cherries (Optional): Place halved maraschino cherries in the center of each pineapple ring and in any gaps between the rings. Press them gently into the brown sugar mixture.

Step 2: Make the Cake Batter

1. Preheat Oven and Prepare Pan (If not already done): Preheat your oven to 350°F (175°C). If you haven’t already melted the butter in the baking pan, ensure your pan is ready with the caramel base as described in Step 1.
2. Combine Dry Ingredients: In a medium bowl, whisk together 2 1/2 cups all-purpose flour, 2 teaspoons baking powder, and 1/2 teaspoon salt. Whisking ensures the baking powder and salt are evenly distributed throughout the flour.
3. Cream Butter and Sugar: In a large mixing bowl or the bowl of a stand mixer, cream together 1 cup (2 sticks) of softened unsalted butter and 1 3/4 cups granulated sugar until light and fluffy. This process incorporates air into the batter, which is crucial for a tender cake. Cream for 3-5 minutes until the mixture is pale and fluffy.
4. Beat in Eggs: Beat in 2 large eggs, one at a time, making sure each egg is fully incorporated before adding the next. Beat in 1 teaspoon of vanilla extract.
5. Alternate Wet and Dry Ingredients: Gradually add the dry ingredients to the wet ingredients in three additions, alternating with the milk or buttermilk in two additions, beginning and ending with the dry ingredients. For example: Dry ingredients (1/3), milk (1/2), dry ingredients (1/3), milk (1/2), dry ingredients (1/3). Mix on low speed until just combined after each addition. Be careful not to overmix the batter, as this can lead to a tough cake. Mix until just combined – a few streaks of flour are okay at this stage.
6. Final Mix: Mix on low speed for a few seconds longer to ensure everything is fully incorporated and the batter is smooth.

Step 3: Assemble and Bake the Cake

1. Pour Batter Over Topping: Gently pour the cake batter evenly over the prepared pineapple and caramel topping in the baking pan. Spread the batter to the edges of the pan using a spatula.
2. Bake: Bake in the preheated oven for 40-50 minutes, or until a wooden skewer inserted into the center of the cake comes out clean. The baking time may vary depending on your oven, so start checking for doneness around 40 minutes. The cake should be golden brown and spring back lightly when touched.
3. Cool Slightly: Remove the cake from the oven and let it cool in the pan for about 10-15 minutes. This is crucial for allowing the caramel to set slightly, making it easier to invert the cake without the topping sticking to the pan.

Step 4: Invert and Serve

1. Invert the Cake: Place a serving platter or large cutting board over the top of the baking pan. Carefully and confidently invert the cake onto the platter in one swift motion. Be cautious as the pan will be hot and there may be some hot caramel syrup.
2. Remove Pan: Gently lift the baking pan off the cake. If any pineapple or cherries stick to the pan, carefully remove them and arrange them back onto the cake.
3. Serve Warm: Serve the Caramelized Pineapple Upside-Down Cake warm for the best flavor and texture. The warm caramel will be deliciously gooey.