Preheat the oven to 180°C and grease and line a baking dish.
In a large bowl, sift the flour and salt together and add the butter. Using your fingers, rub the butter into the flour until it resembles crumbs. Add the milk to the dry ingredients and use a flat bladed knife to mix until a shaggy dough forms. Add the chopped chocolate and gently start to knead it into the dough.
Turn the dough out onto a lightly floured surface and gently knead it until it just comes together and the chocolate is mixed through. Roll out the dough until it’s about 25cm x 40cm rectangle.
Mix the brown sugar and cinnamon together, then spread the dough with butter, leaving a 2cm gap along the long side of the dough and sprinkle with the cinnamon sugar mixture.
Roll the dough from the long edge (not the side with the gap). Slice the roll into 8 pieces.
Place the slices in the prepared baking dish cut side up and bake for 15 minutes or until the tops are just starting to turn golden brown.
Make the glaze while the rolls are baking by mixing together the melted butter and maple syrup with the icing sugar. Add a pinch of salt to taste.
Once the rolls are cooked, drizzle the glaze over the top. These rolls are best served immediately while still warm and the chocolate melty, but they will keep in the fridge covered for up to three days and can be reheated with a little zap in the microwave.