Preheat your oven to 350°F (175°C).
Melt the butter in a 9-inch round cake pan.
Sprinkle brown sugar evenly over the melted butter.
Arrange pineapple slices on top of the brown sugar.
Place a maraschino cherry in the center of each pineapple slice.
In a bowl, whisk together flour, baking powder, and salt.
In another bowl, beat eggs and granulated sugar until light and fluffy.
Add milk and vanilla extract to the egg mixture and mix well.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Pour the batter over the pineapple and cherries in the pan.
Bake for 40 minutes or until a toothpick comes out clean.
Let it cool for 10 minutes, then invert onto a serving plate.