1.In a bowl, combine soy, sugar, garlic, ginger, onion, wine, vinegar, sesame oil, spices and chilli oil. Add pork, turning to coat. Cover and chill for 30 minutes.
2.Heat oil in a large wok on high. Remove pork from marinade, draining well. Reserve marinade for sauce. Sear pork for 5 minutes, turning, until browned on all sides.
3.Return reserved marinade to wok with stock. Reduce heat to low. Simmer, partially covered, for 20-25 minutes, until pork is cooked.
4.Remove pork from sauce and slice. Serve with sauce, rice and greens.
Shaoxing wine is a Chinese rice wine that is available from specialty Asian food stores. If unavailable, you can use sherry instead. Black vinegar is a rich Chinese vinegar that is available from specialty Asian food stores. Balsamic vinegar can be used instead.