Pour the melted butter into a 9 or 10-inch round cake pan.
Sprinkle the brown sugar evenly over the butter.
Place the pineapple slices to cover the bottom of the pan.
Arrange a maraschino cherry in the center of each pineapple ring and in between the rings.
Preheat the oven to 350F (175C).
In a large bowl, whisk together the melted butter, brown sugar, and granulated sugar.
Add the egg, vanilla, milk, pineapple juice, and Greek yogurt. Whisk until combined.
Stir in the baking powder, baking soda, and salt.
Gradually add the flour and mix until just combined. The batter should be thick.
Pour the batter over the arranged pineapple and cherries in the pan.
Bake for 40-45 minutes, or until a toothpick inserted into the center comes out clean.
Let the cake rest for 5-10 minutes in the pan to absorb the syrup.
Run a knife around the edges to loosen, then invert onto a serving dish.