Melt the butter and sugar together in a pan and stir until the sugar has entirely dissolved.
Pour the hot mixture over the chocolate and stir to combine. Add the cocoa and set aside to cool slightly.
Preheat the oven to 200°C/400°F.
Divide the dough into 6 balls and roll out into sausages. Using a rolling pin roll these flat and spoon some of the chocolate mixture down the middle. Pinch up the sides with your fingers and roll again.
Lay three sausages of chocolate stuffed dough and weave the other three between them, making an X shape with each arm consisting of the ends of three dough sausages. Plait each of these together and curl them underneath the ball to make your loaf.
Brush the whole loaf with melted butter and then sprinkle with the sugar.
Bake for 20 minute, or until the whole thing looks golden and lovely. Cool a little and eat when still warm.