To Make the Bun Dough
- Sift the two types of flour together along with the icing sugar. Place the sifted flours and icing sugar together in a mixing bowl and make a well in the middle.
- Combine the vinegar, lukewarm water and yeast together before pouring them slowly in to the middle of the flour well and mixing.
- Add in the vegetable oil and knead the dough for about 10 minutes or until the dough is soft and smooth.
- Cover the dough with a damp towel and let it rise for about 30 minutes and has doubled in size.
- Dissolve baking powder in cold water and pour over the dough while kneading it until they are both well combined.
- Divide the dough in to roughly 16 equally sized portions and roll out in to 3 inch circles.
To Make the Pork Filling
- While the dough is rising, heat oil in a pan and saute the onions for about 2 minutes to soften them before adding in the char siu, sugar, oyster and soy sauce and sesame oil.
- Stir the ingredients well until they are evenly mixed. If the dish isn’t red enough, you can choose to add 1 to 2 drops of red food colouring in to the filling.
- Mix together the water and cornflour before adding them in to the pork filling and continuing to cook until the sauce has thickened to a gravy like consistency.
- Remove the pan from the heat and let cool until the assembly of the buns.
To Make the Pork Buns
- Place a heaped tablespoon of the pork filling in to the centre of one of the bun circles and wrap it in a circular pleat like manner. Continue until the bun has been sealed.
- Place a small circle or square of baking paper on to the bottom of the bun to stop it from sticking to the steamer before placing them in to it.
- Continue to fold the rest of the buns remembering to leave a gap in between each bun in the steamer.
- Bring a saucepan or wok of water to a roiling bowl before placing the steamer on top. Steam the buns for about 12 minutes ensuring that the top of the steamer remains closed to trap all of the moisture.
- After the buns have cooked, allow them to cool slightly before serving!