Steamed Beef Balls (Ngao Yuk)

Ingredients:
 * 1 pound minced beef
 * pinch baking soda
 * 1/3 tsp. dried citrus peel*
 * 3 tsp cornstarch
 * 1/2 cup cold water
 * 2 tsp vegetable oil
 * pinch white pepper
 * 1/4 tsp salt
 * 1/2 tsp chicken bouillon
 * 1/2 tsp sugar
 * a few drops sesame oil
 * 1 tsp oyster sauce
 * Bunch watercress

Preparation:
 * 1) Add baking soda to beef and mix well. Let stand for 3 or 4 hours in fridge. Then soak citrus peel in warm water until soft. Drain and mince finely. (Guide Note: Dried citrus peel or dried tangerine peel can be purchased in Chinese/Asian markets. If you use fresh citrus peel, the orange flavor will be stronger.)
 * 2) Pick up beef in hand and form into a large ball. Then throw the beef with some force into a large bowl 10 or so times. This makes the beef less crumbly when cooked. Alternatively, you can add a beaten egg to the mixture.
 * 3) Dissolve cornstarch in cold water. Stir well and add to beef.
 * 4) Add minced citrus peel, oil, white pepper, salt, chicken bouillon, sugar, sesame oil and optional egg, leaving oyster sauce until last.
 * 5) Form beef balls of about 2 tablespoons of beef in your cupped hands and roll lightly.
 * 6) Line a large dish with lots of watercress. Put beef balls on top. If you're using small dishes, the beef can be steamed in batches.
 * 7) Steam on high heat for 8 minutes after water has come to a boil.
 * 8) Serve with a soy/maggi sauce mixture.