Braised dishes are often served with a creamy side like mashed potatoes, polenta, or grits. Black beans offer an earthy change of pace and complement the chile purée.
Put beans in a 4-to 5-quart heavy pot with enough water to cover by 2 inches.
02Bring to a boil and boil 2 minutes, then remove from heat and let stand, covered, 1 hour.
03Wipe anchos clean, then stem and seed. Discard ribs and tear anchos into pieces.
04Soak anchos in boiling-hot water until softened, about 20 minutes. Transfer anchos to a blender, reserving soaking liquid.
05Purée anchos with onion, garlic, chipotles with sauce, tomato paste, molasses, cumin, cloves, 1/3 cup water, and 1 teaspoon salt.
06Pat ribs dry and season with 1 1/2 teaspoons salt and 1 teaspoon pepper (total). Heat oil in a wide 6-to 8-quart heavy pot over medium-high heat until it shimmers. Brown ribs in batches, about 6 minutes per batch. Transfer as browned to a platter. Discard fat from pot.
07Preheat oven to 350°F with rack in middle.
08Cook bacon in pot over medium heat until browned, then transfer with a slotted spoon to platter.
09Stir chile purée into fat in pot (it may spatter). Cook, stirring frequently, 6 minutes. Stir in reserved chile-soaking liquid, remaining 2 cups water, and cinnamon stick and bring to a boil. Return ribs and bacon to pot and braise, covered, in oven until ribs are very tender, 3 to 3 1/4 hours. Skim fat from sauce.
10Drain beans, then return to pot and add fresh water (8 cups), bay leaf, and 1/2 teaspoon salt. Bring to a boil, then reduce heat and simmer, uncovered, until beans are just tender, 1 1/4 to 2 hours (depending on age of beans). Drain just before serving.