Place flour and butter in a bowl and rub in butter with your finger tips till they resemble fine crumbs.
Stir in castor sugar and enough cold water to form a firm dough.
Wrap in cling film and chill in the refrigerator for 30 minutes.
Preheat the oven to 375 F.
Roll out the dough on lightly floured surface to 13 inch round. Grease lightly 9`` tart pan with removable base.
Line the base of the tart pan with the rolled pastry. Press sides of dough to bring up 1/4 inch above the sides of pan.
Arrange the apple slices over the pastry. Sprinkle sugar with spice over the apples. Grate the butter over the top and bake in a oven.
Bake tarts till the apples are tender. Cooking time ranges to 1 hour and 10 minutes.
Remove apple tart from oven and cool. Serve and enjoy.