In a large mixing bowl or mixer with a dough hook attachment, completely dissolve yeast and sugar in the lukewarm water. Add the flour and knead for about 15 minutes. The dough should be pretty soft and not too firm. If it seems dry, add a little more water. Cover the mixing bowl with a damp kitchen towel and let it proof one hour.

Combine the ground pork, sesame oil, light soy sauce, cooking oil, white pepper, and salt, and mix for a few minutes, until the meat mixture resembles a fine paste, then set aside.

Heat a couple tablespoons of oil in a pan over medium heat and cook the grated carrots for a few minutes until they turn color. Let cool completely.

Combine the pork mixture, the cooked carrots, chopped scallion, ginger, salt, sesame oil, and shaoxing wine. Mix until the entire mixture resembles a paste.

After the dough has finished proofing, turn it out on a clean surface dusted with flour. Knead for 2 minutes to get rid of any air pockets. Roll the dough into a long tube and rip off chunks of dough to make individual dough balls.

Take each dough ball, and with a rolling pin, roll from the edge towards the center, without actually rolling the center of the dough. Add some filling to the center of each disk.

Fold the buns with one hand holding the skin and filling, and the other hand pleating the edges of the dough disk like an accordion. Seal it at the top.

Lay the buns on a floured surface while you finish assembling them. Let the buns proof under a clean kitchen towel for another 15 minutes before cooking or freezing.

To cook, you can steam or pan-fry the buns. For steaming, use a bamboo steamer and steam for 12-15 minutes for smaller buns and 15-20 minutes for larger ones.

For pan-frying, pre-heat a flat-bottomed pan, add oil, and cook the buns until golden brown. Add water, cover, and let steam until the water evaporates.