Prepare the filling: Wash and finely chop the cabbage, peel and shred the carrots, chop the scallions, and grate the ginger. Place the chopped cabbage and carrots in a large bowl, sprinkle with a little salt, toss gently, and set aside.

Place the ground pork in another bowl. Add all the seasonings and grated ginger except for the water. Stir in one direction with a spoon or chopsticks until the mixture becomes sticky. Then add the water and continue mixing until fully absorbed. Cover and refrigerate the filling.

For the dough: Place all the dough ingredients except the oil (keep sugar, salt, and yeast separate) in a bowl. Mix until a dough forms, then add the oil. Knead until the oil is fully incorporated and the dough is smooth and not sticky. Cover with plastic wrap and let rest for about 30 minutes.

Knead the rested dough until smooth. Shape it into a log and divide into small pieces (about 2 ounces or 60 grams each).

Squeeze out excess liquid from the salted cabbage and carrots. Add all the vegetables and scallions to the pork mixture and mix well. Divide the filling into portions of about 2 ounces (60 grams) each. You will have some filling left over; you can refrigerate it and steam it later or use it in other dishes.

Roll each piece of dough into a round wrapper, thinner at the edges and thicker in the center. Place a portion of filling in the center. Hold the bun in your left hand, gently securing the filling with your thumb, and use your right hand to pleat and pinch the dough closed.

Cover the shaped buns with plastic wrap and let them rise again for about 40 minutes, or until they are about 1.5 times their original size.