Squab pigeons take a surprisingly long time to cook - 40 minutes for a relatively small bird - but the legs will be ready at the same time as the breast. Remember to take out the wishbones.
Soak the haricots for at least 2 hours, and preferably overnight. Boil the soaked beans until tender - this should take 20 minutes, but may take longer if you are using other types of dried white haricot bean.
Brush the pigeons with olive oil, then seal in a hot dry pan. Brush once more with olive oil, then transfer to a roasting tray and