1. Lay out 8 12-by-12-inch pieces of heavy-duty foil on a countertop. Divide fruit evenly among foil pieces, placing it on bottom half of foil pieces. Mix sugar and cinnamon together. Put 2 cloves on each square and sprinkle with sugar mixture. Dot each with 1/2 Tbsp. butter and 1/2 Tbsp. rum, if desired. Fold top half of foil over fruit and roll edges to seal.
2. Preheat grill to low. Place packages on grill and cook for 10 minutes. Remove from heat and let cool for 5 minutes. Carefully open packages, pour into bowls and serve with ice cream or whipped cream, if desired.