MIX the sugar, paprika, chili powder, salt, and garlic powder in a medium bowl. Rub all surfaces of meat generously with the dry mixture. Place ribs in the prepared dish in a single layer. Cover and chill the ribs in the refrigerator 30 minutes to 1 hour.
PREHEAT grill to medium indirect heat. Centre ¼ of the ribs and two ice cubes on a sheet (12x18 inches) of ALCAN® Ultimate Grilling Foil with the non-stick (dull) side toward food. Bring up foil sides. Double-fold top and ends to seal packet, leaving room for heat circulation inside. Repeat to make four packets.
GRILL packets on a grill rack over medium (375-400˚F) indirect heat in covered grill 1.5-2 hours or until tender.
OPEN packets carefully by cutting along top folds with a sharp knife, allowing steam to escape; then open top of foil packet. Brush ribs with ½ cup barbecue sauce. Continue grilling over direct medium heat, covered, 5 minutes more until browned and crisp, turning once.
SERVE with additional barbecue sauce as desired.