Take a medium sized pot and put on LOW to MEDIUM heat. Add the BBQ sauce to the pot and bring to a simmer. Add the chocolate, allowing it to slowly melt into the BBQ sauce.While the sauce is heating up, seed the chipotle peppers and add them to the sauce, along with all the remaining ingredients. Allow to simmer for 30 minutes. Remove from heat and blend until smooth. (Put through strainer for a smoother, more refined sauce.)Cool and store in the refrigerator.