Salt cod — bacalao in Spanish, bacalhau in Portuguese, baccalà in Italian, klippfisk in Norwegian — is Atlantic cod (Gadus morhua) that has been heavily salted and dried into a stiff, ivory board that keeps for months without refrigeration. Salting and drying strip most of the water from the already lean flesh and concentrate its protein and savour, so that reconstituted salt cod is a firmer, denser, far more intensely flavoured fish than fresh cod: deeply savoury, mineral and cured, with a chew and a depth the fresh fish never has. It must be soaked for a day or more in several changes of water before it is cooked, and on that soaking hangs a whole family of cuisines — the brandade of Provence, the bacalao al pil-pil of the Basque Country, the ackee and saltfish of Jamaica and the more than a thousand bacalhau dishes of Portugal.