Note Guanciale is cured pig's cheek or jowl. It is available from select Italian delicatessens and butchers.
Few dishes identify a country as strongly as pasta does Italy, and the most popular primi piatti you're likely to find on trattoria menus in the Eternal City is bucatini all'Amatriciana (originally from Amatrice in Lazio). But the recipe we've given here is that of its ancestor, pasta alla Gricia, from the town of Grisciano. Rome has adopted these dishes as its own, and the use of local produce, namely Pecorino Romano and guanciale, is key to their success. With so few ingredients, substitutions should be avoided, but, while it's not traditional, a few basil or flat-leaf parsley leaves make a nice addition.