Core and peel a granny smith apple. Melt one tablespoon of butter (per apple). Add a generous sprinkle of cinnamon (about 1/2 to 1 tsp) and about a tablespoon of brown sugar. Mix thoroughly, then combine with about 1/4 cup of raisins. Set the apple on a square of foil and use a spoon or spatula to pack the core hole with the butter/raisin mix. Add any extra around the apple and seal the foil pack. Bake 15 minutes over indirect heat when grilling (about 450 degrees) or longer when smoking.