Remove fat from beef. Cut beef into 6 serving pieces. Spray 12-inch skillet with cooking spray; heat over medium-high heat. Cook beef in skillet about 8 minutes, turning once, until brown.
In 3- to 4-quart slow cooker, layer beef, onions, garlic and gingerroot. In small bowl, mix broth and soy sauce; pour over beef.
Cover; cook on Low heat setting 7 to 9 hours or until beef is tender.
In small bowl, mix cornstarch and water; gradually stir into beef mixture. Stir in bell peppers. Increase heat setting to High. Cover; cook 10 to 12 minutes or until slightly thickened. Stir in tomatoes. Cover; cook about 3 minutes longer or just until tomatoes are thoroughly heated. Serve over rice.