When butchers break down a side of pork, they are after the several lean cuts of meat, the bones that can be used in stock or sold as dog treats, and the large pile of trim that can be ground into sausage meat. The only parts that typically go to waste are the head, the glands (particularly prevalent in the jowls, but also in the hind legs), and the skin.
Progressive (or retrogressive?) eaters don’t have a problem with pig head, and the glands represent a very small amount of waste, maybe 100g on a side of pork. That leaves the skin. While it can be put into a broth or cassoulet, there happens to be a much more dignified use.
I recently came across a recipe for cotechino, a common boiling-sausage from Emilia-Romagna that is traditionally made with a significant amount of pork skin (“cotica” is Italian for “skin”). The following process is based on the cotechino recipe in Paul Bertolli’s Cooking by Hand.
1: Cut the sheets of skin into manageable squares. The pale squares below are fresh belly skin from my last batch of pancetta. The darker squares are belly skin that was cut from bacon immediately after smoking.
4: Grind the skin through a small die.