Sift the flour into a bowl and stir in the sugar. Gently heat the butter and milk together and as soon as the butter has melted stir the liquid into the flour to make a soft but not sticky dough. Turn it onto a floured surface and kneat it lightly. Divide the dough in half then roll the halves out directly onto a baking tray into 9-inch rounds using a large plate as a guide. Flute the edges. Cut out a 2-inch circle from the centre but leave it in place. Divide the outer ring into eight, keeping the inner circle whole. Sprinkle with granulated sugar and bake at 180 °C (350 °F) for about 30 minutes or until golden brown and crisp.