1. In a 3-1/2- or 4-quart slow cooker, combine beef stew meat and onions. Add bouillon cubes or dry onion soup mix. Sprinkle cornstarch, salt, and pepper over beef and onions. Pour red wine over beef mixture in cooker.
2. Cover and cook on low-heat setting for 10 to 12 hours or on high-heat setting for 5 to 6 hours.
3. If desired, serve over hot cooked noodles. Makes 6 servings.