Preheat oven to 350 °F.
Drain the crushed pineapple. Set aside juice.
Cut the butter into slices and melt in skillet.
Once butter is melted, remove from heat and mix in brown sugar. Allow to cool a bit.
Using a spatula, spread the brown sugar mixture up the sides of the skillet. This will give a base for you to put pineapples on the side of the cake.
Line the skillet with pineapple rings. Make sure to cover the bottom of the pan and as much of the sides as you can. Place a maraschino cherry in the center of each ring.
In a mixing bowl, combine cake mix ingredients per box instructions. Replace water with pineapple juice.
Add the crushed pineapple and mix well.
Slowly pour the cake batter into the skillet as not to disturb the pineapples. Smooth the top with a spatula.
Bake until a toothpick comes out clean. I have a smaller skillet which produced a thicker cake and took about 75 minutes to cook.
Allow cake to cool 5-10 minutes and then carefully flip onto a plate.