Preheat oven to 180 degrees C. Finely grind the almonds in a food processor.
In a medium bowl, cream the butter and sugar together. Mix in ground almonds and egg white. Stir in the flour. Roll dough into 3cm balls and press into biscuit moulds. Place moulds on a baking tray and bake for 12 to 15 minutes. Cool slightly before removing from moulds. Gently tapping the moulds on the counter will help to loosen the biscuits.