Basque Country, Spain
The Basque leek and potato soup — as simple and defined as any preparation in the Basque Country. Porrusalda (from Basque porra — leek, salda — broth) is made from leeks, potato, and occasionally carrot and bacalao, cooked in water or a light chicken stock until the potato has partially dissolved and the leek has surrendered its sweetness into the broth. Nothing else. The result is a pale, gently flavoured, deeply comforting soup that demonstrates the Basque principle that a single excellent ingredient, properly cooked, requires no embellishment. Porrusalda with bacalao (porrusalda con bacalao) adds shredded desalted salt cod in the final 5 minutes — transforming a simple vegetable soup into a complete main course.
Sweat the leeks (the white and pale green parts only) in olive oil until very soft before adding liquid — 15-20 minutes. The potato (diced, 1cm) is added with the liquid (water or light stock) and cooked until it partially breaks down and thickens the soup slightly. Season simply — salt only. The leek must be completely tender and almost melting. For the bacalao version, the desalted shredded cod goes in off the direct heat and finishes in 5 minutes of residual heat.
The simplest version of porrusalda is the most elegant — leek, potato, water, salt, olive oil, nothing else. The bacalao version should use the soaking liquid (partially or fully) as the cooking liquid — it adds depth and the characteristic bacalao salinity. A drizzle of good olive oil and a slice of warm Idiazábal on top is the traditional Basque garnish. Pair with young Txakoli or white Rioja.
Rushing the leek softening — raw-tasting leeks produce a harsh soup. Using the dark green leek tops — they add bitterness. Over-seasoning — porrusalda is a quiet, restrained soup. Adding cream — this is not a cream soup.
The Basque Book by Alexandra Raij