Ingredients:

8 oz beef tenderloin (thinly sliced)
2 tablespoons cooking oil
2 stalks leeks (sliced diagonally)
1 inch ginger (finely chopped)
3 cloves garlic (thinly sliced)
1 stalk shredded green onions (white part only for garnishing)

Marinate:
1 teaspoon corn starch
1 teaspoon soy sauce
1 tablespoon water
1 teaspoon Chinese cooking wine (rice wine or Shaoxing wine)

Sauce:
2 teaspoons oyster sauce
2 tablespoons sweet soy sauce
1/2 teaspoon dark soy sauce
3 dashes white pepper powder
1/8 teaspoon sesame oil
1/4 teaspoon Maggi seasoning
Salt and sugar to taste

Method:
Marinate the beef slices with the seasonings for 30 minutes. Heat up a wok with 1 tablespoon of oil and stir-fry the marinated beef until they are half-done. Dish out and set aside.

Heat up another 1 tablespoon of oil and saute the garlic and ginger until aromatic. Add the beef back into the wok and then the sauce. Continue to stir-fry until the beef slices are almost done, then add the leeks into the wok. Do a few quick stirs, add salt and sugar to taste, dish out and garnish with the shredded green onions.

Serve hot.