In a large mixing bowl, combine all-purpose flour, instant dry yeast, sugar, salt, and roasted sesame seeds. Create a well in the center and pour in warm soy milk and toasted sesame oil. Mix until a dough forms, then knead on a floured surface for about 10 minutes until smooth and elastic. Place the dough in a lightly oiled bowl, cover with a damp cloth, and let it rise in a warm spot for about 2 hours, or until doubled in size.

While the dough rises, soak the vermicelli noodles in boiling water for about 5 minutes until soft. Drain and chop them into small pieces. In a large skillet over medium heat, add neutral oil and sauté shredded cabbage, scallions, and finely shredded carrots for about 5–7 minutes until softened. Stir in the chopped noodles, soy sauce, and seasoning; cook for an additional 2 minutes, ensuring everything is heated through. Allow the filling to cool before using.

Once the dough has risen, turn it out onto a floured surface. Divide the dough into 12-16 equal pieces and roll each piece into a ball. Flatten each ball and roll it out into a thin circle about 3-5 inches in diameter. Keep the rolled wrappers covered with a damp cloth to prevent drying out.

Take a wrapper and spoon a generous amount of the filling into the center. Carefully fold the edges over the filling, pinch them together, and twist to seal tightly.

Heat a non-stick skillet over medium heat and add a drizzle of neutral oil. Arrange the buns in the skillet, crease-side down, and cook for about 3-4 minutes until golden brown. Carefully add water to the skillet, cover immediately with a lid, and steam for 6–8 minutes.

Remove the buns from the skillet and serve immediately while hot. Pair them with a dipping sauce made from soy sauce mixed with sugar and chili if desired.

If you have any leftovers, store them in an airtight container in the refrigerator for up to 5 days.