Combine beef, water chestnuts, cornstarch, garlic and teriyaki sauce. Marinade ingredients for 15 min.
Drain and reserve sauce.Cook frozen vegetables as directed.
Use a 12" skillet or wok . Heat oil to medium high heat. Add beef, garlic, chestnuts & green onions. Stir frequently as beef cooks. Approximately 5 minutes.
Add cooked Asian vegetables and reserved sauce.Continue to stir until mixture thickens. Serve over cooked rice.