Preheat your oven to 350°F (175°C).

In a 9-inch round cake pan, melt the butter in the oven. Once melted, remove the pan and sprinkle the brown sugar evenly over the melted butter.

Arrange the drained pineapple slices over the brown sugar, placing a cherry in the center of each slice for added color and flavor.

In a mixing bowl, whisk together the flour, baking powder, and salt. Set aside.

In another bowl, cream the softened butter and granulated sugar together until light and fluffy, about 2-3 minutes.

Add the vanilla extract and eggs to the butter mixture, beating until well combined.

Gradually add the dry ingredients to the wet mixture, alternating with the whole milk and reserved pineapple juice. Mix until just combined, being careful not to overmix.

Pour the batter over the arranged pineapple and cherries in the cake pan, spreading it evenly.

Bake in the preheated oven for 35-40 minutes, or until a toothpick inserted into the center comes out clean.

Allow the cake to cool in the pan for about 10 minutes before inverting it onto a serving plate. Let it cool completely before slicing.