In a small bowl, combine the first 9 ingredients; set aside. Cut ribs into serving-size pieces; place on a broiler pan. Sprinkle with pepper. Broil 4-6 in. from the heat for 3-5 minutes on each side or until browned; drain on paper towels.
Place ribs in a 5-qt. slow cooker; top with tomato juice mixture. Cover and cook on low for 6-7 hours or until meat is tender.
In a small bowl, combine cornstarch and cold water until smooth. Pour 1 cup cooking liquid into a small saucepan; skim off fat. Bring to a boil; stir in cornstarch mixture. Return to a boil; cook and stir for 2 minutes or until thickened. Serve over ribs.