To make German lebkuchen, mix brown sugar, flour, baking powder, almonds and an egg in a bowl. Cover the bowl, and allow it to sit overnight. Roll the dough, and cut it into rectangles. Bake at 400 degrees Fahrenheit for 12 minutes until firm, and brush with lemon glaze while still warm.
The ingredients for this recipe are 1 egg, 3/4 cup of brown sugar, 1/2 cup of honey, 1/2 cup of dark molasses and a 1/2 cup of sifted confectioners' sugar. Additional ingredients include 3 cups of all-purpose flour, 1/2 teaspoon of baking powder, almonds, nutmeg and cloves.
Combine the egg, brown sugar and honey in a bowl, and beat until smooth. Stir in the molasses. Add all the other ingredients, and cover the dough. Allow it to sit overnight. Preheat the oven to 400 degrees Fahrenheit, and grease the cookie sheets. Roll the dough on a lightly floured surface, and cut into 2-by-3-inch rectangles. Place the rectangles on the cookie sheets, and bake in the oven for 12 minutes or until firm.
Brush the cookies with lemon glaze while they are warm. To make the lemon glaze, combine egg white, lemon zest, lemon juice and confectioners' sugar, and stir until smooth.