Make a paste by working three-fourths pound of butter into one pound of flour, with three-fourths pound of light brown sugar, one egg, one teaspoon of cinnamon, and a pinch of salt. Next mix one-half pound of finely chopped citron peel with one-half pound of ground almonds, and three ounces of butter. Then flavor with one-half teaspoon of vanilla and bind with the yolks of two eggs. Roll out the dough and divide into two parts. Place one-half on a well-buttered flat pan and spread the mixture over it and cover with the other half of the paste. Brush with beaten egg, sprinkle with poppy seed and bake in a moderately quick oven for one-half hour. When done let cool and then cut into square or oblong pieces. The butter cakes may be made of one layer of dough sprinkled with citron and almonds and some poppy seed.