Scrape down three ounces of the best and purest chocolate, or prepared cocoa. Cut up, into a deep pan, three-quarters of a pound of fresh butter; add to it a pound of powdered loaf-sugar; and stir the butter and sugar together till very light and white. Have ready fourteen ounces (two ounces less than a pound) of sifted flour; a powdered nutmeg; and a tea-spoonful of powdered cinnamon - mixed together.
Beat the whites of ten eggs till they stand alone; then the yolks till they are very thick and smooth. Then mix the yolks and whites gradually together, beating very hard when they are all mixed. Add the eggs, by degrees, to the beaten butter and sugar, in turn with the flour and the scraped chocolate, - a little at a time of each; also the spice. Stir the whole very hard. Put the mixture into a buttered tin pan with straight sides, and bake it at least four hours. If nothing is to be baked afterwards, let it remain in till the oven becomes cool. When cold, ice it.