To make the dough, dissolve the yeast in the warm water in a bowl and sit in a warm place for 5 minutes or until completely dissolved and starting to bubble.
Sift the flour and cornstarch and add it to the yeast mixture along with the sugar and oil.
Beginning with a spoon combine the ingredients until they come together.
Using clean hands knead the dough inside the bowl before turning it out on to a clean surface to knead.
Continue kneading until the dough forms a smooth ball (around 10-12 minutes).
Place the dough in a large clean bowl, cover with a damp cloth or cling wrap and rest for 2 hours in a warm place. The dough will double in size.
After 2 hours, add the baking powder to the dough mixture (add a little water if needed) and knead again to combine thoroughly.
Form in to a ball again and rest for another 15 minutes.
While the dough is resting the first time, heat oil in a wok or frypan.
Add the garlic and sauté for 30 seconds.
Add the onion, celery and carrot and cook for 1 minute.
Add the Chinese five spice and stir through.
Add cooking wine.
Add the tamari, red miso, maple, and hoisin sauce.
Finally, add the mushrooms and kale and cook for two minutes or until just cooked.
Take off the heat and set aside to cool.
Cut 10 12cm x 12cm squares of baking paper or parchment.
When the dough has rested a second time, roll it out into a long log shape.
Cut the log in to 10 equal portions. Working one at a time, press each portion down with your palm in to a disc.
Roll out the disc to palm size round making the outer edges thinner than the middle.
With the disc in your palm, spoon a tablespoon of the filling in to the centre.
Following the video (the link is in the above post) fold the edges up and pleat the dough until the top comes together. Twist to finish.
Repeat with the other dough portions placing each one on it's own piece of parchment.
Bring a 1/4 pot of water to the boil and place a bamboo steamer on top being careful to make the sure the water doesn't touch the steamer base.
Place the dumplings in the steamer and cook on a high heat for 12 minutes.