In a large mixing bowl, combine all-purpose flour and salt, creating a well in the center. Pour in hot boiling water and mix until a shaggy dough begins to form. Knead the dough on a floured surface for about 10 minutes until smooth and elastic. Allow to rest for 30 minutes, covered with a damp cloth.

Press the firm tofu to remove excess moisture, then crumble it into a bowl. Sauté green beans in a pan over medium heat for 1-2 minutes until slightly tender. Combine the crumbled tofu, sautéed beans, chopped carrot, cilantro, sesame oil, salt, and white pepper in a bowl, mixing well. Shape the mixture into 10 equal patties.

After the dough has rested, roll it into a log and cut into 10 equal pieces. Flatten each piece into a circle, then place a tofu patty in the center. Pleat the edges to seal the bun. Dab a little water on top and press sesame seeds onto each bun.

Heat oil in a non-stick pan over medium-high heat. Place the buns flat-side down and fry until golden brown, about 3-4 minutes. Add hot water to the pan, cover with a lid, and reduce heat to low-medium. Steam for 3-5 minutes or until the water has evaporated.

Once cooked, remove the buns from the pan and let them cool for a minute. Garnish with chopped green onions and serve with soy sauce or your favorite dipping sauce.