Soak the haricots over night, if possible; if not, at least for two or three hours. Put them on in plenty of cold water seasoned with salt and an onion, and boil them steadily for three hours. Strain the water off, put them into a vegetable dish, and pour over them some parsley butter sauce. Haricot beans are the most nutritious of all pulse foods, and are a particularly good food for people who work in the open air. They are very nice eaten alone or served with meat. They make an exceedingly delicious dish if boiled for two hours and then put into a nice brown gravy and simmered for about an hour. Serve in the gravy with roast mutton.