1. COMBINE the milk, sugar and yeast and stand in a warm place for 10 minutes or until frothy on top. Stir into the sifted flour and salt along with the butter and egg. Turn out onto a floured surface and knead for 10 minutes or until smooth and elastic. Set aside in a greased bowl, covered, for 1-2 hours or until doubled in size.
2. ROLL out the dough on a lightly floured surface to form a rectangle 35cm x 30cm (approx.2cm thickness). Brush the dough with extra melted butter then sprinkle over chocolate and blueberries. Roll up from the long side to enclose the filling then cut into 12 even pieces. Place cut side up in a greased and lined 30cm x 25cm baking pan. Loosely cover and set aside for a further hour or until doubled in size.
3. BAKE in a hot oven 200°C for 25-30 minutes or until cooked and golden. Stand 10 minutes before turning out on to a wire rack to cool. Drizzle with a little icing if desired.