Instructions

1. Put the water, sugar, cocoa and spices into a heavy-based pot. Heat it gently until simmering, then turn off the heat.
2. Break up the chocolate bar, then add it to the pan, stir with a whisk until you get a smooth sauce.
3. Add the rosemary and mandarin, let it infuse for 10 minutes.
4. Pour in the wine and warm it up - but do not boil!
5. Add more wine or water if you find it too thick.
6. Serve warm.