I always thought that everyone knew this recipe, then found out that it is not as common as I thought. I learned it when I was first married, many years ago. This recipe is fairly easy and makes a beautiful presentation when served in a footed glass. A Grapefruit Knife is a knife that one end is serrated and curved; the other is a double blade to separate the membranes. Using a grapefruit knife does makes it easier, but either knife will work.
Remove the Membrane from the Grapefruit:
Cut each grapefruit in half. Using either a grapefruit knife or a serrated knife, slice on either side of the grapefruit section, removing the membrane. Then, while taking an inch or so each time, make several trips and go around the perimeter of the grapefruit separating the grapefruit section from the rind. Remove the membrane and leave the grapefruit sections in the rind.
Prepare for Baking:
Set the oven to Broil. Prepare the pan for the broiler: line a baking sheet with aluminum foil (or use 2 metal loaf pans). Do NOT put glass under the broiler.
Prepare the Grapefruit:
Sprinkle each grapefruit half with 2 T. Brown sugar. Add a Maraschino Cherry to the center of each grapefruit half. Place the grapefruit half on the aluminum foil and place it in the oven. Cook for approximately 4-5 minutes, until the outside rind looks brown/black and the brown sugar is bubbly. Note: even though the rind looks a little burned, it's OK. The rind will look that way just because it is dry