From 1922:
Quarter pound butter, 6 oz. sugar, 3 oz. flour, 3 eggs, one teaspoonful baking powder. Beat butter and sugar to cream, add eggs one by one, flour and baking-powder. Bake in sandwich tins in a quick oven for ten minutes. Turn out, cool and join together with butter icing, flavored with coffee. Butter Icing: 2 oz. butter, 5 oz. icing sugar, beat well together and flavor with coffee. This is a delicious cake and keeps fresh for weeks.