For 4 lbs. of shelled beans, allow ¼ lb. of smoked bacon. Put the beans in boiling salted water, and cook for 5 to 8 minutes. Drain, and put them in a saucepan, with the bacon, cut in small pieces, and a sauce made with 2 ozs. of butter, in which 1 oz. of flour has been stirred, and cooked to a light brown, and diluted with ½ pint of boiling water. Simmer till the beans are tender. Then add salt, pepper, a little sugar, chopped parsley and vinegar to taste.