Preheat oven to 350 degrees and grease 13 x 9 pan
Pour melted butter into pan.
Sprinkle brown sugar evenly on top of butter.
Arrange pineapple slices on top of brown sugar.
Place a maraschino cherry in the middle of each pineapple slice (you could also substitute with a pecan for each pineapple slice).
Add enough water to reserved pineapple juice so that the liquid measures 1 cup.
Mix pineapple liquid, cake mix, oil, and eggs in a large bowl on medium speed for approx 2 minutes. Make sure there are no bumps.
Pour cake batter into prepared pan (directly on top of pineapples and cherries).
Bake for 35-40 minutes. Cake will be done when you insert a toothpick and it comes out clean.
Place a heatproof pan/plate upside down and place on top of pan. Holding both the plante and the pan, turn them over together and place the plate right side up on the counter. Keep pan turned upside for 5 minutes.
Remove pan and cool for 30 minutes.
Frost sides of cake with Pineapple Cream Cheese Frosting.
Cover frosting with chopped pecans, if desired.
Serve warm or cool (warm is so much better)!
This doesn't need a garnish, but homemade whipped cream tastes great on the side.