At Franceschetta 58, Bottura's more casual osteria, the chefs riff on dishes from all over Italy using local products—to sometimes mixed reactions from Italian traditionalists. One of the stars is a play on the revered pasta all'amatriciana, born some 2,000 years ago in the mountain town of Amatrice and later adopted by the citizens of Rome. Shepherds found sustenance in this simple pasta with pork, pork fat, and Pecorino Romano. An account from 1816 credits chef Francesco Leonardi for updating the dish, using tomatoes for the first time. He served his newfangled version—with onions and guanciale, cured jowl—to the Pope's court. It's since been considered practically sacred, and the Romans are notoriously touchy about messing with it.