PREHEAT barbecue to medium heat. Place potatoes in centre of 18-inch-long piece of heavy-duty foil. (Or, use a double layer of regular foil.) Drizzle with water and oil. Bring up foil sides. Double fold top and ends to seal packet, leaving room for heat circulation inside.

GRILL 18 to 20 min. or until potatoes are tender.

CUT slits in foil to release steam. Open packet. Drizzle potatoes with dressing; sprinkle with cheese and parsley.