Sardinia’s Liveliest Pecorino

Find out why the prized pecorino called casu marzu, "rotten cheese", is banned by Italian health laws and European Union regulations.

Brooke Slezak

The most common cheese in Sardinia is pecorino, made from sheep's milk; and everywhere you go on the island, you'll see hand-lettered signs announcing formaggio pecorino for sale—from young and fresh to aged (for grating) to smoked. All are readily available. The prized pecorino called casu marzu, "rotten cheese", however, is not. Banned by Italian health laws and European Union regulations, it is basically a pecorino that has been infested with the larvae of flies, which live in and eat the cheese and make it pungent and creamy-chunky in texture. Casu marzu, also known as walking cheese, usually kept in the dark so that the maggots remain dormant, is not sold in stores, but my friend managed to find one for me during my visit. We happened to be in a light-filled room as we prepared to taste it, and the maggots started jumping around like crazy and landing everywhere, including on us. It was quite wild to look at, let alone contemplate eating. I smeared a piece of creamy, leaping cheese on a piece of bread and took a bite. It tasted like an extremely ripe gorgonzola without the blue veining of mold. The maggots? They were as unnoticeable as gnats swallowed on a midsummer night's bicycle ride. Well, maybe not quite.