Prep the pan and oven: Preheat oven to 350°F (175°C). Grease a 9-inch round cake pan or oven-safe skillet. Line the bottom with parchment if you have it.

Make the topping: Melt 1/4 cup butter in a small pan. Stir in brown sugar until dissolved and glossy, about 1 minute. Pour into the cake pan and spread evenly.

Arrange the fruit: Lay pineapple rings over the sugar layer, slightly overlapping if needed. Nestle cherries in the centers if using.

Mix dry ingredients: In a bowl, whisk flour, baking powder, baking soda, and salt. Set aside.

Cream butter and sugar: In a large bowl, beat 1/2 cup butter with granulated sugar until light and fluffy, about 2–3 minutes.

Add eggs and vanilla: Beat in eggs one at a time, then mix in vanilla until smooth.

Combine wet and dry: Stir together milk and pineapple juice. Add dry ingredients to the butter mixture in two parts, alternating with the milk mixture. Mix just until combined. Do not overmix.

Fill the pan: Spoon batter over the fruit and spread gently to the edges. The batter will be thick.

Bake: Bake for 35–45 minutes, until the top is golden and a toothpick comes out clean. If browning too quickly, tent loosely with foil.

Cool and flip: Let the cake rest 10–15 minutes. Run a knife around the edge, place a plate over the pan, and carefully invert. Lift off the pan and peel away parchment if used.

Serve: Let cool slightly. Serve warm or at room temperature. A dollop of whipped cream is lovely.