Take a quarter of a pound of chocolate, melt it by the fire, mix with it the yolks of three eggs, about a quarter of a pound of sugar, two ounces of butter, then two spoonfuls of flour. When all this is well mixed, add the whites of the eggs well whipped. Butter one flat fireproof dish and put in the mixture; it should be about one inch thick. Cook ten minutes in a hot oven. When nicely golden, turn it over in another buttered dish and cook another ten minutes. The inside of the cake should remain soft.