Cook the beans for 40 minutes (2 hours if dried, after a 2-hour soaking). Cut the sausages into short lengths and cook in a frying pan with 2 cloves of garlic and the sage.

Cook slowly, piercing them so that they cook right through. They should be cooked, but crisp, not boiled.

At this point, add the tomato purée, season with salt and pepper and reduce over moderate heat for a further 10 minutes.

Add the beans, draining them well and combine the flavours over gentle heat, stirring carefully with a wooden spoon.