Sift the high-gluten and superfine flours together. Combine sifted flours, salt, milk powder, bread improver and softener in an electric mixing bowl. Stir in sugar. Attach a dough hook and mix for 10-20 seconds. Combine water and yeast in a small bowl, sprinkle over sugar and stir to dissolve. Leave aside to ferment for about 5 minutes.
Pour frothy yeast mixture into the combined flours and add butter and egg. Beat at slow speed for 10-15 minutes until a soft pliable dough is formed. Cover the bowl with a damp tea towel and leave to proof for 45-50 minutes or until doubled in bulk. Remove dough out onto a lightly floured tabletop. Roll out to a rectangle 0.5cm thick.
Beat the egg and honey together lightly with a fork. Brush the dough rectangle with egg and honey mixture and sprinkle with most of the cinnamon powder and soft brown sugar (keep a little for the topping). Combine the dessicated coconut and salt. Keep about 1 teaspoon for the topping and spread the rest over the dough together with the sultanas. Place a few strips of butter liberally around.
Roll the dough tightly, Swiss roll-style, into a long cylinder and cut into even portions. Place each portion into a paper casing. Put the paper casing into a muffin tray. Put into a big plastic bag and leave aside to proof for 30 minutes or until doubled in size. Brush top of the buns with remaining egg and honey mixture. Add an additional sprinkling of remainder desiccated coconut, soft brown sugar and cinnamon powder. Bake in preheated oven at 180°C for 25 minutes or until well risen.