San Sebastián 
The purrusalda (or porrusalda, from the Euskera for ‘leek’ and ‘broth’) has been in the Basque canon for centuries, though there is a lot of disagreement about how it should be made and whether or not it should contain cod – and there is even more debate about its correct form.
It can be served as a thick, robust stew, the vegetables left in chunks; it can be creamed, as in this recipe; or it can be served like a minestrone, a thin soup with diced vegetables. It’s this very versatility that makes it so popular.
‘It’s a comforting dish, a winter dish,’ says Patricio Fuentes, head chef at the San Sebastian Food cookery school. ‘It has always been a dish of survival, too, something that could be rustled up with whatever vegetables were to hand in the caserios.’ Caserios are the traditional half-timbered small holdings that dot the Basque hillsides and still make up an essential element of local life. It is here that the best leeks are to be found, according to Patricio. ‘Leeks should be line, not thick. You only find those in the caseríos – those that are bred for mass production don’t taste of anything.’
‘The leeks are all-important, but aside from that the purrusalda can be whatever you want it to be. Add cod or chicken, or keep it simple. Serve it as a soup or a main course, or spoon it alongside some fish.’
A chronology of culinary history, the purrusalda reflects the changing tastes and availability of ingredients. Potatoes have not been around all that long in Spanish cooking, and carrots were only recently introduced into the dish.
‘When I teach this recipe I am giving a little lesson on Basque social and rural history,’ Patricio adds.
