Preheat oven to 350 degrees F. Butter two 9 inch round cake pans. Sprinkle the bottom of each pan with 1/4 cup (or more-for more good gooey stuff) of brown sugar.
In one of the pans, sprinkle coconut over the brown sugar. Lay pineapple rings in a single layer on top of coconut. Place a cherry in the center of each ring. In the other pan, spread the drained crushed pineapple.
Mix the cake as directed on package, but substitute reserved pineapple juice in place of water. Divide batter between the 2 pans.
Remember which pan has the pineapple rings in it.
Bake for 35 minutes in the preheated oven, or until a toothpick inserted into cake comes out clean. Cool in pans for 20 minutes.
While the bottoms of the cake pans are still warm to the touch, invert the layer with the crushed pineapple out onto a serving dish, then gently invert the layer with the pineapple rings on top of it.