Finely chop or grind almonds (food processor works great). Whip the egg whites in a clean bowl until stiff. Sift the confectioner’s sugar and gradually fold it under the egg whites. Reserve and put aside 2 heaped tablespoons of this mixture. Gently stir the almonds into the egg mixture. Sprinkle the work surface with confectioner’s sugar.
Roll out the mixture to about 1/4 inch thick. Cut out cookies using a star cutter and place them on a cookie sheet lined with non-stick parchment paper. Dip the cutter into confectioner’s sugar from time to time to stop the mixture from sticking to it. Brush each star with a little of the reserved egg mixture.
Bake for about 30 minutes until crisp on the outside. The cookies should still be a little soft in the centre.