Wheat Starch Wrappers (see recipe) Light soy sauce, for Dipping Chinese mustard, for Dipping can be prepared entirely in advance and reheated a few minutes before serving. The wheat starch wrappers have an interesting chewy texture, a unique translucent appearance and are absorbent of flavors. Roll out the wrappers as thin as possible; otherwise they come out rubbery. Cover mushrooms in warm water for 20 minutes or until soft and pliable. Remove and squeeze out excess water from the mushrooms. Cut off the stems at the base and discard them. Finely mince the caps. Toss the shrimp with salt and let them stand 10 minutes. Rinse well with cold water, pat dry thoroughly. Coarsely mince. Preheat a wok or skillet. when hot, add the peanut oil. over mediumhigh heat, add the mushrooms, shrimps, pork butt, bamboo shoots, water chestnuts, and half the green onions; stir-fry until the pork turns white. Season with the sugar, white pepper, wine and soy sauce. Combine the cornstarch and chicken stock in a small bowl and mix until smooth; pour into wok. Stir fry for 1 minute longer. Remove the mixture to a shallow plate and mix in the remaining green onion and coriander. Allow the filling to cool, then refrigerate it until needed. Makes almost 2 cups of filling. Prepare the Wheat Starch Wrapper dough. Pinch off 1-inch balls of dough. Lightly oil the ball and flatten it into a thin 3 1/2-inch circle. An oiled Chinese cleaver is traditionally used; however, a tortilla press or a rolling pin works. Put 1 large teaspoon of filling in the center of the circle. Fold it in half and pinch the edges to seal the filling inside. Repeat with remaining dough and filling. Place dumplings without touching each other on a lightly oiled bamboo steamer (or a heat resistant plate). Steam over boiling water for 3 minutes. Serve hot, dipped in light soy sauce and Chinese mustard. Serve with Chinese Mustard, for dipping. Makes 2 1/2 dozen dumplings.