Finely chop pork, onion, carrot, and green onion.
Mix the chopped pork and vegetables with soy sauce, sugar, pepper, and sesame oil to make the meat filling.
Combine flour, yeast, sugar, and salt, then add water and knead to form dough. Let it rise for 1 hour.
Divide the dough into pieces, roll each piece flat, and place the meat filling in the center.
Place the buns in a steamer and steam for 15–20 minutes until done.