Preheat your oven to 350°F (175°C) and prepare your pan.
Melt the butter and brown sugar in your cake pan over low heat.
Arrange the pineapple slices and cherries in the pan.
In a separate bowl, whisk together the flour, baking powder, and salt.
In another bowl, cream together the melted butter and granulated sugar until fluffy.
Add the egg and mix until combined, then stir in the milk.
Gradually add the dry mixture to the wet mixture, stirring until just combined.
Pour the batter over the pineapple arrangement in the pan, smoothing the top evenly.
Bake for 30-35 minutes or until a toothpick comes out clean.
Let the cake cool for a few minutes before inverting it onto a serving platter.
