Cook rice according to package directions.
Combine pepper, soy sauce, sugar, tomato paste, chicken stock, cornstarch. Set aside.
Cut meat into thin strips, about 2 inches (2.5 cm) long.
To hot
wok
, add beef, ginger, 2 sliced scallions, carrot, celery. Stir-fry 2 minutes, remove to side.
Add sauce to center of pan. Stir beef, vegetables into sauce, toss 1 minute. Remove to serving dish.
Add sesame oil to wok. When hot, add scallions, rice, peas. Toss 1 minute.
Season with salt and pepper to taste.
Pour vegetables over beef in serving dish. Serve over rice. Serves 2.