Step 1 (Blanch Pork): Place pork cubes in a pot of cold water. Bring to a rolling boil and cook for 5 minutes. Drain and rinse under cold water (this removes impurities and tightens the meat). Pat dry with paper towels (critical for proper searing).
Step 2 (Caramelize Sugar): Heat 1 tbsp oil in a heavy-bottomed pot over low heat. Add 50g rock sugar. Cook, stirring constantly with a spatula, for 5-7 minutes until sugar melts into a deep amber liquid. Immediately proceed to next step to avoid burning.
Step 3 (Sear Pork): Carefully add blanched, dried pork to the caramel. Increase heat to medium-high. Stir-fry for 3-4 minutes until all pieces are evenly coated and browned.
Step 4 (Braise): Add 3 tbsp Shaoxing wine, 2 tbsp light soy sauce, 1 tbsp dark soy sauce (for color), 5 ginger slices, 2 green onion pieces, and 2 star anise. Pour in 2 cups hot water (just enough to cover pork). Bring to a boil, then reduce heat to low. Cover and simmer gently for 90 minutes. Check at 60 minutes; sauce should reduce by half.
Step 5 (Reduce Sauce): After 90 minutes, uncover, increase heat to medium. Simmer for another 15-20 minutes, basting pork occasionally, until sauce is thick, glossy, and coats the back of a spoon.
Step 6 (Serve & Store): Serve hot with steamed buns or rice. Garnish with chopped green onion. Store leftovers in the braising liquid in the refrigerator for up to 4 days. Flavor improves overnight. Freeze for up to 3 months. Reheat gently with a splash of water.