The dark greeny-blue French lentilles du Puy are generally considered to have the best flavour and are well worth buying. They have recently been granted appellation d’origine contrôlée status, just like a fine wine or cheese, which means that only lentils from a particular corner of France - the area around Puy-en-Velay in the Haute Loire - are entitled to be called Puy. This decree is causing consternation among some British supermarket chains, which sell ‘Puy lentils’ that have in fact been produced in Canada. If you can’t get the genuine article, don’t worry! Cannellini beans also work very well in this winter salad.