In a small sauce pan bring cream, corn syrup, brown sugar, cocoa powder, salt and half of the chocolate to a slow boil (you down't want it to be bubbly and overflow). Reduce heat and cook for a few minutes stirring occasionally. Remove from heat and stir in the remaining ingredients and stir until it is all combined and smooth. Let cool for 10 minutes before using (it gets thicker as it cools). Store in a jar or airtight container in the fridge for up to 3 weeks (if it lasts that long!). To reheat, microwave for 10-20 seconds.