1. In a jug, stir together the milk, sugar and yeast. Stir until the sugar is dissolved, then allow it to sit, covered, for five minutes.
2. Using an electric mixer, beat the butter until smooth. Add the eggs, one at a time, beating after each addition
3. Add the remaining ingredients to the mixing bowl. Using a dough hook attachment, start mixing on a slow speed for 4-5 minutes. Mix at a higher speed for five more minutes.
4. Add the dough to a lightly greased bowl, cover with cling film and allow to prove in a warm place for at least one hour or until doubled in size.
5.  In a small bowl, stir together the brown sugar, cinnamon and butter. Line a 30 x 20cm tin with parchment paper.
6. Once the dough has doubled in size, transfer to a floured surface. Roll the dough into a 40 x 50cm rectangle. Spread the cinnamon mixture over the rolled dough and sprinkle the chocolate on top.
7. Roll the dough up, starting from the longest side. Cut the dough into 12 even slices. Add the slices into a greased tin with the swirls facing upwards. Cover, and allow to prove for 30 minutes, until doubled in size again
8. Preheat the oven to 180 ̊C/160 ̊C fan/ gas mark 4.
9. Bake for 15-20 minutes or until golden brown. Make sure they are no longer doughy
10. To make the icing, beat all the ingredients together until smooth. Pour the icing onto the cinnamon rolls. Sprinkle orange zest on top to decorate and serve warm.

Per serving: 586kcals, 22.8g fat (11.5g saturated), 88.6g carbs, 44.8g sugars, 8.8g protein, 2.8g fibre, 0.331g sodium