Pulse almond paste in food processor until small crumbs. Pour into large bowl. Stir in confectioners sugar by hand. Whip egg whites until stiff, then fold them into almond paste mixture. If desired, add almond extract. Refrigerate overnight.

Scoop batter into balls, roll in granulated sugar and place on parchment-lined cookie sheet. Press cookies down slightly with the palm of your hand. Bake at 350 degrees for 18 - 20 minutes, or until golden brown. Cool for 5 minutes and transfer cookies to cooling rack.