Parmesan is a hard, granular cow's-milk cheese aged at least a year and often far longer, its straw-yellow paste crumbling into savoury, crystalline shards. Nutty, salty and packed with umami, it is grated over pasta, shaved into salads and chewed in chips alongside aged balsamic. The protected original — Parmigiano-Reggiano — is made by hand from raw milk in a small corner of northern Italy.