Using the pastry hook attachment on a stand mixer, combine the yeast strain in the hot water in the mixing cup.
Combine the cornstarch and flour together, then mix them with the amounts of sugar and oils in the yeast-water mixture.
When a soft dough ball forms, switch the food processor on to a low speed.
Let the flour rest in the bowl for two hours with a moist cloth over it. Remember to add baking powder to the dish afterwards.
Laid back the dough. The meat filling may be made in the interim.
In a wok that has been warmed up, add the diced onions. Gently fry for one minute.
Soy sauce, oyster sauce, dark soy, sesame oil, sugar, and heat to medium-low. Simmer the mixture while stirring until it bubbles.
Add flour and chicken stock, and boil for a few moments until it hardens.
Toss in the chopped Chinese roasting pork after removing it from the heat. In order to prevent drying out, let the filling cool and, if prepared in advance, cover it and place it in a fridge.
After the batter has rested for two hours, stir in the baking powder while mixing at the slowest speed. Add a teaspoon or two of water if the dough seems dry. Mix the batter until it is once more smooth.
For an additional 15 minutes, cover it with a moist cloth and leave it alone.
Ten 4x4-inch pieces were cut from a huge sheet of paper made from parchment. Heating water is an option to prepare your boiler.
Split the batter into 10 identical pieces to form the buns, and then roll each piece into a lengthy tube.
Every dough piece should flatten into a disc with a circumference of about 4/12 inches, with the centre being denser and the outer edges being thinner.
Each disc should be filled with meat before being topped off with a pleated bun.
Put each of the buns on a square of paper made from parchment. In two distinct groups, boil them in bamboo steam. Make sure the buns don't come in contact with the hot water while they are being steamed.
Put your buns in the steaming after the water is boiling, and boil each set for twelve minutes at a time (on high heat).