Oaxacan Green Mole

Yield: 4 to 6 servings. Soak beans in 2 cups water 4 to 8 hours or heat them to a boil 1 minute and then let stand 1 hour. Drain beans; place in a large saucepan with 3 quarts water, pork and bones. Heat to a boil, skim off foam, then add onion and garlic. Cook, partly covered, over medium-low heat, stirring occasionally, until beans and meat are tender, 1 1/2 to 2 hours. (If the liquid level drops below the level of the beans and meat, add hot water.) Meanwhile, heat a griddle or large skillet over medium heat. Put a piece of foil on the hot surface, set the tomatillos on top and roast, turning regularly, until blistered, blackened and soft, 10 to 15 minutes. Remove to a food processor or blender. Roast garlic and chilies directly on the hot surface, turning frequently, until chilies are blackened and blistered, about 5 minutes, and garlic is blackened and soft, about 10 minutes. Scrape black skin off chilies and remove seeds; peel garlic. Add both to the tomatillos; add cumin. Puree. When beans and meat are tender, pour them into a colander set over a large bowl. Pick meat off bones; discard bones, return meat to the colander with the beans; set aside. Skim fat off broth. (There should be at least 5 cups broth; if not, add water.) Set the clean pan over medium-high heat; add lard or oil. When hot enough to make a drop of tomatillo puree sizzle, add it all at once. Stir constantly 4 to 5 minutes as the mixture sears and thickens, then add 4 cups of the broth. Cover and simmer over medium-low heat 20 minutes. Gradually mix 2/3 cup of the remaining broth into masa harina mixture in a small bowl. Push the mixture through a wire mesh strainer into the simmering tomatillo mixture, whisking constantly, until thickened. Add the beans and meat, season with salt and let simmer, stirring occasionally, while you prepare herb puree. For herb puree, put parsley, epazote if using, hoja santa or fennel mixture and 1/3 cup broth into a food processor or blender. Puree, adding a little more liquid if necessary. Stir the herb puree into the bean mixture. Add a little more broth or water if necessary to thin to a medium consistency. Serve in warm, deep plates; garnish with parsley.