Stove top directions: Brown the chorizo in a cast iron dutch oven or other heavy bottomed large pot over high heat, breaking it up into small pieces with a wooden spoon. Do not drain. Add the onion, bell pepper and garlic, cook, stirring, for one minute. Pour in the beef broth, stir in the black beans, tomato paste and cocoa powder. Bring to a boil, reduce the heat to low, cover. Simmer, stirring occasionally, for at least one hour.