Prep: 1. Boil 3 cups of water (to soak chiles in) 2. Seed and remove stems from chiles. 3. Chop: onions and garlic. 4. Preheat oven to 350. Make: 1. Sprinkle meat with 3/4 tablespoon salt and let stand at room temperature while making puree. 2. Soak anchos in 3 cups boiling water to soften, about 15 minutes. Transfer chiles to a blender with a slotted spoon with 1/2 cup chile soaking liquid (reserving remainder). 3. Blend chiles with onion, garlic, brown sugar, chipotles, tomato paste, cloves, and remaining teaspoon salt. Puree until very smooth. 4. Heat oil in a large Dutch oven over medium heat. 5. Add puree and cook, stirring, until it turns a rich brick color, about 8 minutes. Stir in remaining soaking liquid and cocoa. 6. Add pork and cinnamon and bring to a simmer. Cover and braise in oven, basting occasionally, until very tender, 4-6 hours. 7. Skim fat from sauce. If sauce is thin, transfer meat to a bowl and loosely cover. Simmer sauce until thickened. 8. Ease meat from bones with a fork, pour sauce over and serve!
This is a perfect dish for a long, slow Sunday of cooking.