Try to find the French lentils called lentilles de Puy for this dish, as their flavour is far superior to that of other lentils. They are slate grey in colour and are becoming more widely available in supermarkets.

The combination of moist and succulent flakes of fish, the earthiness of the lentils and the sharp punch of the sauce gives this dish a fine balance of flavours. This is one of the most satisfying plates of food I know; both for texture and flavour.