From 1922:
Half a cupful of shortening, 1 cupful sugar, 2 eggs, 1 ¾ cupfuls flour, 3 teaspoonfuls baking powder, 1 tablespoonful cocoa, 1 tablespoonful cinnamon, three-quarters of a cupful milk. Cream shortening, add sugar and yolks of eggs; beat well; sift together flour, baking-powder, cocoa, and cinnamon, add alternately with milk; fold in beaten whites of eggs. Bake in two greased layer tins in moderate oven 35 to 40 minutes, put together with the following whipped cream:
Cocoa whipped cream: One cupful of cream, 4 tablespoonfuls cocoa, third of a cupful powdered sugar, half teaspoonful vanilla extract. Mix cocoa and sugar with a little hot water until well blended; add vanilla and cream, and whip until stiff enough to spread.