Christmas Cinnamon Biscuits

450g (16oz) Flour
225g (8oz) Butter
225g (8oz) Sugar
225g (8oz) Nuts, (Hazel, Brazil, Pecans), finely chopped
1 Egg, separated
1 tbsp Cinnamon

1. In a large bowl, cream the butter, gradually adding sugar, beat until light and fluffy.
2. Add beaten egg yolk. Mix flour and cinnamon.
3. Spread on mixture onto two lightly greased baking trays.
4. Brush slightly beaten egg,.
5. Sprinkle with nuts, patting down lightly.
6. Preheat oven to 170°C: 325°F: Gas 3
7. Bake for 30 minutes.
8. Cut into bars whilst still warm.
9. Do not remove from baking trays until cooled.