In a large mixing bowl, combine all-purpose flour, instant dry yeast, sugar, and salt. Make a well in the center and pour in warm soy milk and toasted sesame oil. Mix until a soft dough forms. Knead for about 5-7 minutes until smooth. Cover and let rise for 2 hours.

Soak vermicelli noodles in boiling water for 5 minutes until softened. Drain and chop. In a skillet, add neutral cooking oil, and sauté cabbage, scallions, and carrot for 4-5 minutes. Add noodles, soy sauce, salt, and sesame oil, cooking for another 2 minutes.

Punch down risen dough and divide into 12-16 pieces. Roll into balls and flatten into 3-5 inch rounds using a rolling pin. Cover with a damp cloth.

Place a spoonful of filling on each wrapper. Pinch edges together to seal the bun tightly. Repeat with remaining wrappers and filling.

Heat a non-stick pan over medium heat and add neutral oil. Arrange buns, crease-side up, and sauté for 5-6 minutes until golden. Flip, add a splash of water, cover, and steam for another 5-6 minutes.

Serve hot, optionally with soy sauce mixed with sugar and chili sauce for dipping.