Make the dough: In a large bowl, combine the flour and salt. Make a well in the center and carefully pour in the boiling water. Stir the mixture with a spatula or chopsticks until it forms shaggy flakes. Once cool enough to handle, knead the dough in the bowl for 3 to 5 minutes to incorporate all the flour. If the dough feels too dry, add 1 tablespoon of cool water at a time. Turn the dough out onto a clean surface and knead until smooth and taut, 10 to 12 minutes. Cover with a bowl or damp towel and let rest for 30 minutes.

Prepare the filling: While the dough is resting, place the tofu in a nut milk bag or over a mesh strainer and squeeze out as much liquid as possible. Transfer the drained, mashed tofu to a large bowl.

Heat the oil in a large skillet or nonstick pan over medium-high heat. Sauté the green beans for about 2 minutes, until crisp-tender and darkened in color. Transfer them to the bowl with the tofu. Add the carrot and cilantro, then season with the salt, white pepper, and sesame oil. Fold and mash the filling into a paste, adjusting the seasoning as needed. The mixture should be slightly saltier than you would eat on its own.

Assemble the buns: Divide the filling into ten equal portions. Roll each portion into a ball with your palms, then flatten into a patty. Keep the patties covered until ready to use.

Turn the rested dough onto a lightly floured surface and knead for about 2 minutes until smooth. Roll the dough into a thick log and divide it into ten equal portions, about 45 to 50 g each. Keep the dough portions covered with a damp towel while you work.

Take one portion of dough and flatten it into a round disc with your palm. Using a rolling pin, roll the edges toward the center, pressing back and forth while turning the dough with your nondominant hand, until the wrapper is 4½ inches (11 cm) in diameter. Leave a quarter-sized “belly” in the center to hold the filling. Place a heaping tablespoon of filling in the center, leaving a ¾-inch (2 cm) border of dough around it. Pinch the edges together around the filling like closing a pouch, sealing tightly with a final pinch.

Prepare one plate with water and another with toasted sesame seeds. Lightly dab the smooth side of each bun in water, then press it into the sesame seeds. Place the bun on a floured surface. Repeat with the remaining dough and filling.

Pan-fry the buns: Heat a large skillet (about 12 inches / 30.5 cm) over medium heat. Add 1 tablespoon of oil, or enough to coat the bottom of the pan. Arrange the buns sesame-side down in the pan.