The wontons can be prepared ahead of time up to the cooking stage and refrigerated or frozen. Bring the wontons back to room temperature before deep-frying.
Yields about 48 wontons
1. Wipe any dirt off the mushrooms. Soak in warm water until softened (20 to 30 minutes). Squeeze out the excess water and chop. Wash and shred the bok choy leaf. Wash and dice the green onion. Mince the ginger until you have 1/2 teaspoon.
2. In a medium bowl, combine the ground pork with the dark soy sauce, sesame oil, sugar and salt. Add the lightly beaten egg and the vegetables. This is the wonton filling.
3. Heat the oil to 375 degrees Fahrenheit. While the oil is heating, prepare the wontons. Lay a wonton wrapper in front of you. Place a teaspoon of the filling in the middle. Fold up the wonton so that it resembles a nurse's cap, wetting the edges to seal (if you haven't made wontons before, see photo instructions on filling wontons).
4. Add the won tons to the hot oil, a few at a time, sliding them in carefully. Deep-fry the wontons in batches until they are golden brown, turning to make sure they brown evenly. Drain on paper towels or a tempura rack if you have one. As with egg rolls, wontons should be served as soon as possible, to ensure they remain crispy. Serve with Sweet and Sour Sauce or red rice wine vinegar.