This is a sophisticated dish made from port which is cooked base on the technique of Chinese people in Lang Son and became a Lang Son specialty long time ago. People usually make khau nhuc (khau nhục) for luxury meal or to welcome guests from far.
Khau nhuc making requires people to be elaborate from the meat choosing part. Meat should be pork of a 70 to 80kg heavy pig, not too fat one. Pork should be good (peeled-off pork won’t be chosen). Each bowl of khau nhuc is estimated to contain eight pieces, about 0.5 to 0.6 kg; the amount of pork is prepared depending on the number of bowls.
The spices for khau nhuc are also complicated. Tau soi (tàu soi) leaves (a kind of salted vegetable used as food of Chinese,Tay, Nung people in Lang Son) is washed carefully to leave all dirt and salty taste. After that, they are chopped tiny to make the filling, and then mixed with spices including tau choong (tàu choong) sauce, soy sauce, sweet basil flavoring powder, crushed garlic.
Tau soi leaves are lined below, lightly fried taro or sweet potato is put above. People slice pork into pieces which is 1.5 cm thick each one (8 pieces a bowl), arrange pork on the dish forming a circle shape, and then put a big bowl upside down on the dish keeping the dish. Each bowl is put in the pot, water bath steamed in 3 to 4 hours to make pork over-cooked and soft. When preparing the meal, khau nhuc that is still hot is carried out for enjoying.