1. Trim the fat and slice the beef into 1/8 inch thick strips (cross grain). 2. Combine the soy sauce, ginger, garlic, and basil. Add the beef and toss to coat. Set aside to marinate for at least 30 minutes. 3. Cut up your vegetables and set aside. 4. Heat the oil in a large pan. Add the beef and brown over high heat. Lower the heat and cover. Simmer the meat for about 30 minutes or until tender. Be careful not to let the meat dry out. If you need to, add a bit of water for moisture. 5. Add the peppers, celery and green onion to the meat. Toss over high heat until heated but still crisp. This will take about 10 minutes. 6. Mix the cornstarch with the water. Stir this into the meat mixture and cook until thick. 7. Add the tomatoes and heat through. 8. Serve over rice and enjoy!