Some cuts and pieces of Guanciale are very lean, taking in a good deal of the muscle strips in the cheek and jaw. Others will be fattier than streaky bacon or American-style bacon, and seem like a strip of meat sandwiched in between two layers of fat.
The meat is formed into a block that is triangle shaped, then buried or covered in salt, sugar, saltpetre and spices and let sit in a cool place for a month. It is then hung to dry for another month, sometimes two months, with whatever salt coating is on it still adhering to it.
Spices used in the cure include a generous amount of either black pepper or dried chile, so the meat becomes a bit spicy.
Though the meat is cured, it still needs cooking. It is very flavourful and used as a flavouring agent, rather than as a “bacon” you would fry up for breakfast.
Guanciale is made in Latium, the region that Rome is in. In making a Carbonara sauce, someone who lives in Rome would use Guanciale, not pancetta. Guanciale is hard to find outside Italy, but don’t feel bad: not even Italians outside Latium can find it easily.
Pancetta or unsmoked bacon.
Guancia means “cheek” in Italian