2.Heat half the oil in wok; stir-fry prawns, in batches, until changed in colour.
3.Heat remaining oil in wok; stir-fry garlic, chilli and peppercorns until fragrant. Add choy sum; stir-fry until wilted. Return prawns to wok with sauce, wine, sugar and chestnuts; stir-fry 2 minutes. Remove from heat; stir in onion and nuts.
Kung pao, a classic Sichuan stir-fry, is made with either seafood or chicken, peanuts and lots of chillies. An authentic Sichuan-Chinese restaurant always has a delicious kung pao.