How do you make pork bun?

* For the dough:

* 2 cups all-purpose flour

* 1 tablespoon sugar

* 1 teaspoon baking powder

* 1/2 teaspoon baking soda

* 1/2 teaspoon salt

* 1 cup water

* 2 tablespoons vegetable oil

* For the filling:

* 1 pound ground pork

* 1/2 cup chopped onion

* 1/2 cup chopped green cabbage

* 1/2 cup chopped carrots

* 1/4 cup soy sauce

* 1 tablespoon oyster sauce

* 1 teaspoon sesame oil

* 1/2 teaspoon white pepper

* For the glaze:

* 1 egg yolk

* 1 tablespoon water

Instructions:

1. Make the dough: In a large bowl, whisk together the flour, sugar, baking powder, baking soda, and salt. In a separate bowl, whisk together the water and vegetable oil. Add the wet ingredients to the dry ingredients and stir until just combined. Do not overmix. The dough should be slightly sticky.

2. Knead the dough: Turn the dough out onto a lightly floured surface and knead for about 5 minutes, until smooth and elastic. Place the dough in a greased bowl, cover with plastic wrap, and let rise in a warm place for about 1 hour, or until doubled in size.

3. Make the filling: In a large skillet, heat a little oil over medium heat. Add the ground pork and cook until browned. Add the onion, cabbage, and carrots and cook until softened. Stir in the soy sauce, oyster sauce, sesame oil, and white pepper. Cook for 1 minute more, or until the sauce has thickened. Remove the skillet from the heat and let the filling cool slightly.

4. Assemble the buns: Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper. Punch down the dough and divide it into 12 equal pieces. Roll each piece of dough out into a 4-inch circle. Place a spoonful of filling in the center of each circle. Fold the dough up over the filling and pinch the edges together to seal. Place the buns on the prepared baking sheet.

5. Bake the buns: Brush the buns with the glaze and bake in the preheated oven for about 15 minutes, or until golden brown. Serve the buns hot.