Parmesan gets all the glory when it comes to pairing cheese with pasta. And there's no question: Authentic Parmigiano-Reggiano, in all its many subregional variations, is one of civilization's great cow's milk treasures. But for nearly half Italy, from Rome south, Pecorino is the hard cheese of choice. There is an extra edge of farmyard piquancy to these cheeses made from the milk of sheep, which flourish in harsher terrains, that has a way of cutting through sauces with an alluring rustic swagger. But which Pecorino to use? To begin with, Pecorino is a generic name for all Italian cheeses made from sheep's milk, and it's produced in all stages of ripeness and methods across every region of southern Italy, including the island of Sardinia (where it's called fiore sardo), as well as Tuscany to the north, where it tends to be younger.
Pecorino Romano is the classic hard cheese for grating, and it's a personal favorite, though there are many grades here, too, including plenty of industrial pregrated dust that can be so sharp I find it too harsh. The best I've tasted recently comes from Genuine Pecorino Fulvi, which, according to Emilio Mignucci at Di Bruno Bros., is "one of the very last true Roman Pecorinos made in Lazio from whole sheep's milk." That higher butterfat distinction, vs. cheeses made from skim milk, allows this cheese to be slightly moister and less salty than others without sacrificing bold flavor. When broken up, it can give the unusual sensation of being simultaneously powdery and creamy. In fact, the bone-white paste on our skinny wedge was so delicate it was hard to grate without crumbling. So I crushed it by hand, ate it in chunks, and then sprinkled the rest over pasta, to which it added a bright and tangy full sheep richness to every bite.
— Craig LaBan