In a large mixing bowl, combine 3 cups of all-purpose flour, 1 packet of instant dry yeast, 1 tablespoon of sugar, and a pinch of salt. Create a well in the center and pour in 1 cup of warm soy milk and 2 tablespoons of toasted sesame oil. Mix until a shaggy dough forms, then knead for about 8-10 minutes until smooth. Cover with a damp cloth and let it rise in a warm place for 2 hours, or until doubled in size.

While the dough rises, soak 1 cup of uncooked vermicelli noodles in boiling water for about 5-7 minutes until soft; drain and set aside. In a large skillet, heat 2 tablespoons of neutral oil over medium heat. Sauté 2 cups of raw shredded cabbage, 1 shredded carrot, and ¼ cup of chopped scallions for 4-5 minutes until the vegetables soften. Stir in the drained vermicelli noodles, 1 tablespoon of soy sauce, and season to taste before allowing the filling to cool.

Once the dough has risen, punch it down and turn it onto a floured surface. Divide the dough into 12-16 equal pieces and roll each into a ball. Using a rolling pin, flatten each ball into a thin round wrapper, about 4-5 inches in diameter. Keep the wrappers covered to prevent drying out.

Take one wrapper and place a generous spoonful of the cooled filling in the center. Carefully gather the edges of the dough around the filling, pinching and twisting to ensure a secure seal. Repeat for each wrapper, making sure all buns are tightly sealed. Arrange on a plate, seam side up.

In a large non-stick skillet, heat 2 tablespoons of neutral oil over medium-high heat. Carefully place the buns in the skillet, creased side down, and pan-fry for about 4-5 minutes until golden brown. Add ½ cup of water to the skillet, cover immediately, and steam for 5-6 minutes until fully cooked and fluffy. Remove the lid for the last minute to evaporate excess moisture before serving.

Transfer the buns onto a serving plate. Garnish with roasted sesame seeds if desired. Best enjoyed hot, paired with a zesty soy dipping sauce.