Preheat oven to 350 degrees. Spray your muffin tins with non-stick cooking spray.
In a mixing bowl, add eggs, white sugar, and pineapple juice. Beat for 2 minutes. In a separate bowl, sift together the flour, baking powder, and salt. Add to the wet ingredients and turn mixer back on for 2 minutes.
In a small sauce pan, melt the butter and add the brown sugar. Stir on low heat for one minute.
Spoon a layer of the warm brown sugar mixture into the bottom of each muffin tin, then place a pineapple ring on top. Add a cherry in the middle of each pineapple. Pour cake mixture over to fill muffin tin 3/4 of the way full. If you are using regular muffin tins, you will need to cut down the rings to fit or just use pineapple tidbits.