Rub the butter and the flour together until like crumbs. Stir in the sugar. Bring the mixture together and knead lightly until the mixture forms into soft dough. Shape into biscuits and cook on a greased baking sheet for about 30 minutes (or until it looks cooked) on Gas Mark 3 / 165 degrees C / 325 degrees F. When cooked remove from tray and leave to cool on a wire rack.