In a large mixing bowl, combine wheat flour, sugar, milk, and oil. Knead until the mixture is smooth and elastic. Let the dough rise in a warm place until it doubles in size, around 1 hour.

In a separate bowl, combine ground pork with chopped vegetables and optional seasonings. If desired, add eggs for added richness. Taste and adjust seasonings with salt and any spices you prefer.

Divide the risen dough into smaller pieces, flatten each piece into a circle, and place a spoonful of the filling in the center. Gather the edges and pinch them together to seal each bun securely.

Carefully place the assembled buns in a steamer lined with parchment paper. Steam for 15-20 minutes, or until the dough is firm and fluffy to the touch.

Remove the buns from the steamer and serve them warm. They are perfect to enjoy right away or can be stored for later!