1. Combine ground beef, onion, egg and salt in medium mixing bowl; mix well. Shape into 18 (1-inch) meatballs. Place in 9-inch round glass baking dish. Cover with plastic wrap.
2. Microwave on ROAST for 8 minutes. Drain drippings. Combine remaining ingredients in small mixing bowl. Pour over meatballs and continue cooking on ROAST for 5 to 6 minutes or until piping hot.