Ingredients for 5 servings:
1. 1 lb beef flank steak or 1 lb boneless sirloin steak
2. 1 tablespoon vegetable oil
3. 1 teaspoon cornstarch
4. 1 teaspoon salt
5. 1 teaspoon sugar
6. 1 teaspoon soy sauce (light or dark)
7. 1/8 teaspoon white pepper
8. 1 lb bok choy (about 7 large stalks)
9. 2 green onions (with tops)
10. 2 tablespoons cornstarch
11. 2 tablespoons cold water
12. 3 tablespoons vegetable oil
13. 1 teaspoon gingerroot, finely chopped
14. 1 teaspoon garlic, finely chopped
15. 3 tablespoons vegetable oil
16. 1/2 teaspoon salt
17. 1/2 cup chicken broth
18. 2 tablespoons oyster sauce or 1 tablespoon dark soy sauce

Directions:
1. Trim fat from beef; cut beef with grain into 2-inch strips.
2. Cut strips across grain into 1/8-inch slices.
3. Toss beef, 1 tablespoon vegetable oil, 1 teaspoon cornstarch, 1 teaspoon salt, the sugar, soy sauce and white pepper in glass or plastic bowl.
4. Cover and refrigerate 30 minutes.
5. Separate bok choy leaves from stems.
6. Cut leaves into 2-inch pieces; cut stems diagonally into 1/4-inch slices (do not combine leaves and stems).
7. Cut green onions into 2-inch pieces.
8. Mix 2 tablespoons cornstarch and the water.
9. Heat wok until 1 or 2 drops of water bubble and skitter when sprinkled in wok.
10. Add 3 tablespoons vegetable oil; rotate wok to coat side.
11. Add beef, gingerroot and garlic; stir-fry until beef is brown, about 3 minutes.
12. Remove beef from wok.
13. Add 3 tablespoons vegetable oil to wok; rotate to coat side.
14. Add bok choy stems; stir-fry 1 minute.
15. Stir in bok choy leaves and 1/8 teaspoon salt.
16. Stir in chicken broth; heat to boiling.
17. Stir in cornstarch mixture; cook and stir until thickened, about 15 seconds.
18. Stir in beef and oyster sauce; heat to boiling.
19. Garnish with green onions.

Enjoy your meal!