Place the flour, almonds and orange peel in the food processor, and process until all the ingredients are finely ground. Add baking powder, salt and spices.
Whisk together eggs and brown sugar, add flour mixture in thirds and stir with a wooden spoon until incorporated.
Chill dough overnight, or until firm.
To form the cookies, on a floured surface, roll a piece of dough about the size of a golfball into a rope.
Using a dull knife (I like the shape created from the slight flattening of a dull knife) such as a butter knife, cut the ropes into lengths of approximately 1 inch.
Place the cookies 1 inch apart on parchment lined cookie sheets, and optionally allow to dry overnight.
Preheat oven to 350 and bake the cookies about 15 minutes or until brown around the edges.
While the cookies are still warm, toss in powdered sugar.
Ripen for a week in an airtight container with a slice of apple.