Add flour, yeast, baking powder, sugar, salt to the bowl or a stand mixer. Slowly pour in the milk and mix with a spatula. Knead for 10 minutes until you get a smooth dough.

Cover the bowl with plastic wrap or damp cloth and rest the dough until it doubles in size, about 1 hour.

Cut 10 pieces of square parchment paper approx 7cm X 7cm, to be used while steaming the baos.

Once the dough has doubled in size, punch the dough down with your hand to release the air and knead for a minute.

Cut the dough into 2 equal pieces, and divide each piece into 5 smaller pieces.

Work on the dough pieces one at a time shaping them into a ball. Place the dough balls on a large plate and keep them covered with a damp cloth to prevent drying.

Working on one dough ball at a time, use a rolling pin to roll the ball into a ¼″ (½ cm) thick oval. Flip the dough oval over and lightly roll again to smooth it out.

Brush the top of the dough oval with a thin layer of oil (refer note 1), fold the oval in half, and place on a piece of parchment paper prepared earlier.

Place the shaped baos on the parchment paper pieces & keep on a steamer plate, leaving some gap between the baos. Do not overcrowd the plate as they expand & stick together. Cover with damp cloth and let rise for 15 to 30 minutes before cooking, or until the size is 1.5 times bigger.

Bring the steamer to a boil. Before steaming the baos, brush them lightly with oil. Place the steamer plate with the risen baos in the steamer. Place a kitchen towel between the steamer plate and the lid to prevent water from dripping on the baos. Cook over medium heat for 10 - 12 minutes.

After 10 minutes, turn the heat off but leave the lid on for another 5 minutes. The baos might deflate slightly if you don’t rest them for 5 minutes before opening the lid.

Remove the baos on a wire rack to cool. Then you can use the same steamer to steam the rest of the baos.

Steam the baos in batches depending on the size of your steamer. While you’re steaming the first batch of the baos, transfer the rest of the baos to a greased plate and cover them with damp cloth.

Stuff the baos with a filling of your choice and serve.