Peel the potatoes and put them over the fire in cold water. Bring to a boil and cook until tender. Turn off the water, cover them with warm milk, and stew ten minutes. Transfer the potatoes to a vegetable dish, thicken the milk in which they were cooked with a teaspoonful of butter rolled in a tablespoonful of flour, and season with salt, pepper, and minced parsley. Pour this over the potatoes, pressing each with a spoon so as to crack it.