This warm spiced lentils dish really makes the most of the intense, slightly bitter flavour of cavolo nero. It is unusual to see these earthy ingredients combined with exotic spices, but it does work. I like this as a main course but you can also use it as a side to accompany lamb, chicken, sausages or even a substantial fish, such as sea bass. I use Puy lentils for their nutty flavour and firm texture – plus the little gleaming, dark greeny-grey pebbles look beautiful with the cavolo nero leaves. Make this with vegetable stock if you prefer, for a completely vegetarian dish.