Rinse pickled mustard greens under running water. Then soak them in plenty of water for 2 hours or overnight (see note 3).
Drain and squeeze out any excess water. Cut them into tiny pieces.
Fry the pork
Heat 1½ tablespoons of oil in a wok or a large skillet over high heat. Stir in the ground pork.
Use a spatula to break and loosen any large lumps, and toss to fry until the meat loses its pink color.
Add Shaoxing rice wine, light soy sauce, and dark soy sauce. Stir fry for 10 more seconds then dish out and set aside.
Combine the dish
Pour the remaining ½ tablespoon of oil into the wok/skillet. Add most of the scallions (keep some for garnishing), garlic, ginger, and chilies. Sizzle until fragrant.
Put in the chopped pickled mustard greens. Toss for one and a half minutes or so. Then put the pork back into the wok. Mix and fry for a further 30 seconds.
Add sesame oil, sugar, white pepper, and the remaining scallions. Give everything a thorough stir before dishing out to serve.
Video
Notes
1. To substitute pickled mustard greens, you may use other types of Chinese “sour vegetables”, such as pickled cabbage, pickled napa cabbage, pickled radish/daikon, or pickled asparagus beans/long beans.2. No matter which meat you use, it’s better to choose ground meat with a high fat content.3. Pickled mustard greens of different brands vary in their flavor intensity. So the required soaking time may differ. Taste and adjust if unsure.