Coat slow cooker with cooking spray.
Combine all ingredients except cornstarch in slow cooker; mix well. Cover and cook 7 to 8 hours on low or 4 to 5 hours on high, or until meat and vegetables are tender.
With sloted spoon, transfer beef and vegetables to serving bowl cover with foil to keep warm.
Turn cooker on high. Combine cornstarch with 2 tablespoons water; mix well. Stir into juices; cover and cook 15 minutes or until thickened.
Spoon sauce over beef and vegetables.