Briefly blanch spinach then transfer to a food processor to puree.
Use a fine sieve to extract approximately 75 ml / 5 tablespoons of spinach juice (add anlittle water if necessary). Set the spinach puree aside for the filling.
Make the dough in two colours
Divide the flour into two equal portions. Add about 75 ml / 5 tablespoons of water to one portion of flour then knead to a white dough.
Add the spinach juice to the other portion of flour to form a green dough.
Leave to rest for at least 30 minutes (see note 2).
Mix the filling
Mince Pak Choi (Bok choy), carrot, Shiitake mushroom and mung bean vermicelli noodles (chop with a knife or use a food processor).
Squeeze out the excess water from the vegetables with your hands.
Stir in the spinach puree and egg.
Place spring onion, ginger and ground Sichuan pepper on top of the mixture. Heat up the oil then pour it over the herbs and spice.
Finally, add salt and mix(see note 3).
Roll the wrappers
Roll the white dough into two ropes.
Flatten the green dough into two rectangle pieces (same length as the ropes) then wrap the white dough all round and seal well.
Cut into about 40 equal sections. Press each piece into a small disc with the palm of your hand.
Use a rolling pin to flatten it into a thin disc. Dust with flour if the dough sticks (Please refer to the video in the post).
Shape the dumplings
Place a spoonful of filling in the middle of a wrapper.
Fold the wrapper, then seal it. You may do it any way you like. Make sure there is no leakage if you plan to boil (instead of frying) the dumplings.
Fry the dumplings
Coat a frying pan with oil and heat up over high heat. Place in the dumplings.
When the bottom part becomes golden brown, pour in water (enough to cover ⅓ of the dumplings) then cover with a lid.
Uncover when the water evaporates completely. Serve warm with a dipping sauce of your choice.
Notes
1. How to rehydrate shiitake mushrooms: soak them in cold water for at least 8 to 12 hours (depends on the size) until very soft. Trim and discard the stem before using.2. The ideal flour water ratio may vary slightly depending on the brand of the flour and how you measure it (Measuring flour with cups is less accurate). To make wrapper rolling easier, the dough shouldn’t be too soft.3. Do not add salt to the filling until the moment you are about to assemble the dumpling. This is because salt will draw extra liquid from the vegetables and you don’t want the filling to be too wet.4. Make in advance: freeze dumplings right after they are assembled. Firstly you need to lay them on a tray (dust with flour or line with parchment paper) to freeze. Then put them in an air-tight bag when totally frozen. Follow the same cooking procedure (do not defrost).