Steps to Make the Cake:

• Preheat your oven to 350°F (175°C). Grease your 9-inch round cake pan with a little extra butter, ensuring it's well-coated so the cake releases easily once baked.
• In a small bowl, combine the melted salted butter and packed brown sugar. Mix until well combined. Pour this mixture into the bottom of your prepared cake pan. Arrange the drained pineapple slices on top, and place a maraschino cherry in the center of each pineapple ring. Set this aside while you prepare the batter.
• In a large mixing bowl, whisk together the all-purpose flour, baking powder, and salt. In another bowl, cream together the softened unsalted butter, granulated sugar, and the remaining brown sugar until light and fluffy. Add in the egg and beat until well combined.
• Stir in the sour cream, milk, and reserved pineapple juice into the butter and sugar mixture until smooth. Gradually add the dry ingredients into the wet mixture, mixing just until combined. Avoid over-mixing to keep your cake light and fluffy.
• Pour the cake batter over the pineapple and cherry topping in the cake pan, spreading it evenly. Bake for 35-40 minutes or until a toothpick inserted into the center comes out clean.
• Once baked, remove the cake from the oven and let it cool in the pan for about 10 minutes. After that, carefully invert the cake onto a serving plate. The pineapple and cherry topping should be beautifully displayed on top of the cake.