Sift the flour, salt and mixed spice into a basin. Add the butter cut in pieces and rub into the flour. Add the sugar and sultanas and mix. Lightly mix the egg and milk and pour into the centre of the ingredients. Using a fork mix to a rough dough. The mixture should be fairly firm.
Pile the mixture into twelve rough heaps on greased baking trays, not too close together, since they flatten out slightly on baking. Sprinkle a little demerara sugar on the top of each one. Place in the centre of a moderately hot oven (200°C., 400°F., Gas Mark 6) and bake for 10–15 minutes, or until lightly browned. Loosen the base of each with a palette knife and cool on a wire tray.