First make the candy cane template. On paper draw a walking stick, 1 cm (½ inch) wide and 10 cm (4 inches) long, with a curved end, then cut it out. Roll out the biscuit dough on a lightly floured surface. Lay the template over the dough and cut around it about 25 times using a small, sharp knife or scalpel.
Space the shapes slightly apart on greased baking sheets. Re-roll the trimmings to make extras. Bake in a preheated oven, 180°C (350°F), Gas Mark 4, for 15 minutes or until pale golden. Transfer to a wire rack to cool.
Put the royal icing in a pastry bag fitted with a plain nozzle and pipe a zig-zag line of icing along each cookie. Leave the cookies in a cool place to set for at least 1 hour before serving.