Mix together the dry dough ingredients, then add enough water to bring it to a dough. Knead for 10 minutes or until smooth.
Cover the dough and let it rise somewhere warm for 60-90 minutes, or until doubled in size.
Add all of the filling ingredients, except the chicken stock, to a food processor. Pulse a few times until it’s roughly chopped and starting to bind together. You don’t want it to get to a smooth paste or there will be no texture in your dumpling filling.
Add the chicken stock a tablespoon at a time, pulsing briefly each time to incorporate it into the mixture.
Cover and chill while you wait for the dough.
When the dough is ready, knock it back then tip it out and divide into 20 balls.
Working with one at a time, roll it out to around 10cm across.
Put one tablespoon of filling in the middle, then shape in the sheng jian bao style - crimping with your right thumb and forefinger, and using your left hand to turn the dumpling as you go.
Heat 2 tbsp of oil in a large flat-bottomed frying pan.
Add the dumplings - put some facing up and some facing down for two different effects.
Once the dumplings start to brown underneath, pour in the water and cover with a bamboo steamer lid.
Wait for the water to evaporate and the steam to stop - this should take 8-10 minutes.
Remove the lid and serve the dumplings immediately, with sesame, spring onion and soy sauce.