Trim excess fat from pork chops and sprinkle with rosemary and salt and pepper to taste. In a heavy 10-inch skillet heat oil over moderately high heat until hot but not smoking and saute pork chops until browned on both sides, about 5 minutes. Transfer pork chops with tongs to a plate. In drippings remaining in skillet saute onion until it begins to brown. Add water, vinegar, and jelly and bring to a boil, stirring until jelly melts. Simmer mixture, covered, over moderate heat until onion is tender, about 5 minutes. Return pork to skillet and cook, uncovered, turning once, until cooked through and almost all liquid is evaporated, about 5 minutes. Serves 2. Gourmet December 1994