We may use the more meaty front end of the belly as a roasting joint but in Cantonese cuisine crisp crackling is highly prized so they happily roast the more fatty rear belly for this dish.
It is also worth noting that if the bellies are on the thick side chef Kwun Fu of Fung Shing in Soho London trims away the lean meat until he has a thin sheet about 2cm thick. The fat and the crackling are much more important than the meatiness - a most refreshing attitude in these cholesterol-conscious times!
A sheet of pork belly about 25cm square and 2cm thick
1tbs spiced salt (made from 2 parts salt, 1 part powdered ginger, 1 part five spice powder, ¼ part ground white pepper ½ part crumbled star anise)
Make a pattern of cuts across the meat side of the belly and rub in 1tbs spiced salt. Turn over and prick the skin side all over with a fork.
Rub in the juice of a lemon and 1tbs salt. Hang the joint in a dry airy place for 24 hours. When you are ready to cook preheat the oven to its maximum temperature and roast the belly for about 45 minutes.
The meat must be hung in the oven that way the fat can drip off freely. The belly is particularly delicious eaten cold.