1.Add peeled and grated ginger, crushed garlic and oil to frying pan, saute gently for one minute. Add hoi sin sauce, oyster sauce, soy sauce and sesame oil; simmer for two minutes, stirring constantly.
2.Add combined water and cornflour, stir until sauce boils; reduce heat, simmer uncovered for two minutes. Add very finely chopped pork, stir until combined. Remove pan from heat, add finely chopped shallots, stir until combined. Allow pork mixture to become completely cold.
3.To make the dough, sift flour, salt and baking powder into bowl. Rub in softened lard until mixture resembles fine breadcrumbs. Add combined warm water and vinegar, stir to a soft but pliable dough. Turn out on to lightly floured surface; knead lightly. Cover dough with plastic food wrap, allow to stand for 20 minutes. Knead again lightly. Cut dough into 12 equal portions. Roll each portion into a ball.
4.Take each ball of dough and roll out on floured surface to a 10cm (4in) circle. Brush edge lightly with water.
5.Place one round of dough in palm of hand. Put one teaspoon of filling in centre of round. Press edges of dough together.
6.Take the two ends of bun, bring them up over the pinched edge and twist together firmly.
7.Cut 12 pieces of greaseproof paper into 12cm (5in) squares. Brush one side lightly with oil. Place a bun upside down, so the smooth rounded side is uppermost, on each oiled piece of paper.
8.Choose a saucepan slightly smaller than the diameter of the steamer you are going to use. Fill saucepan about one-third full of water, bring to boil.
9.Arrange buns on paper in single layer in steamer. If using steamer with two or three racks, fill remaining racks in same way.
10.Stack the racks on top of each other and cover with lid. Steam over gently boiling water for 20 minutes. There is no need to change position of racks during cooking time.
These buns are cooked in steamers, available at Chinese stores. They are available in sets of two or three racks. Cost of a two rack steamer is around $10. Chinese barbecued pork can be bought at Chinese food stores; or you can make your own.Note