Prepare aromatics and vegetables: finely mince 1cm ginger (about 1/2 inch), 1 garlic clove, and 1 chili pepper. Finely chop 1 bunch green onion. Put 100g cabbage, 80g carrots, and 40g celery through a blender or grate finely; if the shredded vegetables release a lot of liquid, press or squeeze out the excess.
Make the filling: In a large bowl, combine 800g ground chicken (minced chicken), the shredded cabbage, carrots and celery, the minced ginger, garlic and chili, the chopped 1 bunch green onion, and 60ml soy sauce. Mix until evenly combined. Set the filling aside.
Make the dough: Put 600g white flour and 2g salt in a food processor. Bring 420ml hot water to a boil. With the processor running on low, slowly add the boiling water to the flour until the dough comes together; increase speed and mix until homogeneous. If you don’t have a food processor, pour the hot water into the flour in a bowl and mix, then knead by hand until combined.
Knead and portion the dough: Turn the dough onto a lightly floured surface and knead by hand for about 1 minute until smooth. Shape into a ball and cut it into 8 equal pieces. Cut each of those 8 pieces into 8 more pieces (total 64 pieces). Roll each small piece between your palms to form a ball.
Form wrappers: Flatten each small dough ball in your palm, then roll it into a thin round wrapper with a rolling pin (or press thin with your palm). Keep finished wrappers covered with a damp cloth so they do not dry out.
Fill and seal dumplings: Place about 1 teaspoon of the filling in the center of each wrapper. Fold and seal the edges by pinching, pleating, or pressing with a fork until fully closed. Place assembled dumplings on a tray.
Freeze for storage (optional): Arrange dumplings in a single layer on a tray so they do not touch, freeze until solid, then transfer to zip-lock bags or boxes for longer storage.
Cook dumplings (boiling method): Bring a large pot of water to a rolling boil. Add dumplings in batches without overcrowding and stir gently to prevent sticking. When dumplings float, continue boiling until fully cooked through (about a few minutes). Remove with a slotted spoon. If cooking from frozen, add a little extra cooking time until heated through.
Make the soy dipping sauce: Finely chop 0.5cm ginger (about 1/4 inch), 1/4 garlic, 1/2 chili pepper, and 1 green onion. In a small bowl combine the chopped ingredients with 2 tbsp soy sauce, juice of 1/2 lemon, 1 tbsp honey, 1 tbs price vinegar, and 1 tbsp sesame oil. Stir to combine.
Serve: Serve the cooked dumplings hot with the prepared soy dipping sauce.