Preheat the oven to 350° (180°C) and grease the bundt pan with cooking spray.
In a bowl, mix together the melted butter and light brown sugar until well combined.
Pour the mixture onto the bottom of the bundt cake pan and spread it evenly with a spoon.
Place the 6 whole pineapple slices on the bottom of the pan, with half a slice between them (arch side down) and one maraschino cherry in the center of each whole slice
In a large mixing bowl, mix together the cake mix, eggs, water, vegetable oil, and pineapple juice until well combined
Pour the batter over the pineapples and cherries carefully and evenly. Bake for 35-40 minutes until a toothpick comes out clean.
Remove from the oven, and let it cool down for 10 minutes. Place a plate on top of the pan and flip it to remove the cake.