Created by Derf on October 24, 2011
Step 1: Cut beef across the grain into thin strips; cut strips into 2 inch lengths. In bowl, whisk together cornstarch, sherry and soy sauce until smooth. Add Beef and toss to coat.
Step 2: Heat the oil in a wok to medium, add the beef with cornstarch liquid and stir fry for 2 minutes; add onion and stir fry for 1 minute or until beef is browned. Add garlic and tomatoes; stir fry until tomatoes are heated through, 1 to 2 minutes. Stir in green onions and serve immediately.