Steamed Bun Dough - active dry yeast

Method

• Dissolve the yeast in 1/4 cup warm water.
• Add 1 teaspoon sugar, 1/4 cup flour, and stir to mix well.
• Allow to stand for 30 minutes.
• Mix in remaining warm water, remaining flour and sugar, salt, and lard or vegetable oil.
• Knead until dough surface is smooth and elastic.
• Roll over in a greased bowl, and let stand until triple in size, about 2 1/2 to 3 hours.
• Punch down dough, and spread out on a floured board.
• Sprinkle baking powder evenly on surface, and knead for 5 minutes.
• Divide dough into 2 parts, and place the piece you are not working with in a covered bowl.
• Form each half into a log about 2 inches thick.
• Cut logs into 1-inch pieces and roll each into a ball.
• Cover with a damp towel.
• Working with 1 piece of dough at a time, press into a thin disc shape.
• Place about 1 tablespoon of filling in center, and then gather up edges and twist to seal, using some extra drops of water to stick together as needed.
• Cover with a damp kitchen towel and repeat with remaining dough.
• Line bamboo steamer tray with lettuce or cabbage leaves.
• Place buns, sealed side down, in bamboo steamer tray and let rise for 45 minutes.
• Meanwhile, heat water to boiling in a wok to a level just below the bamboo steamer.
• Place bamboo steamer in wok and steam buns for 20 to 25 minutes, and then remove from heat.
• Remove lid before turning off heat, or else water will drip back onto bun surface and produce yellowish "blister".
• Place a wok over medium heat.
• Add the oil and, when hot, add the ginger, and green onion and stir-fry until aromatic, about 1 minute.
• Add the shrimp and bamboo shoots and cook for 1 minute.
• Add the sugar, soy sauce, and sesame oil and stir to combine.
• Combine the cornstarch and the water and add to the shrimp mixture, stirring frequently.
• The mixture should thicken immediately.
• Transfer mixture to a bowl and allow to cool before assembling the buns.