1In a large bowl, combine all-purpose flour and 3g salt. Gradually add 180g warm water while stirring with chopsticks until a shaggy dough forms. Add 10g vegetable oil and knead the dough on a lightly floured surface for 8-10 minutes until smooth and elastic. Cover the dough with a damp cloth and let it rest for 30 minutes.
2While the dough rests, prepare the filling. Finely mince ginger and garlic. Thinly slice scallions. In a dry wok or pan over medium heat, toast Sichuan peppercorn and dried chili flakes for 2-3 minutes until fragrant. Remove from heat and grind them into a coarse powder using a mortar and pestle or spice grinder.
3In a mixing bowl, combine ground pork, minced ginger, minced garlic, sliced scallions, ground Sichuan peppercorn, ground dried chili flakes, light soy sauce, dark soy sauce, Shaoxing wine, sesame oil, white pepper, and 2g salt. Mix thoroughly in one direction until the filling becomes cohesive and slightly sticky.
