Cream two-thirds cup of butter with two cups of granulated sugar; add one-half cup of milk, yolks of four eggs, one cup of hot mashed potatoes, one cup of chocolate, one teaspoon each of cinnamon, cloves, and nutmeg, one teaspoon of vanilla, one cup of chopped walnuts, two cups of flour, two teaspoons of baking-powder, then beaten whites of four eggs. Bake slowly in two pans, and cut in half when cold. Put jam between layers.
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