How to Make It
In a heatproof bowl, cover the chiles with boiling water and let stand until softened, 20 minutes.
Meanwhile, roast the tomatoes directly over an open flame or under a broiler, turning occasionally, until charred in spots and just starting to soften, 5 to 8 minutes. Transfer to a work surface and let cool slightly, then coarsely chop.
In a large saucepan, heat 1/4 cup of the oil until shimmering. Add the chopped tomatoes, onion, garlic, oregano, cinnamon stick, allspice, cloves and a generous pinch each of salt and pepper. Cook over moderate heat, stirring occasionally, until softened and saucy, 8 to 10 minutes. Let cool slightly; discard the cinnamon.
Drain the chiles, reserving 2 cups of the soaking liquid. Add them to a blender along with the tomato mixture and puree until the mole sauce is smooth. In a large saucepan, heat 1/4 cup of the oil. Add the sauce and bring to a boil. Cover and simmer over moderate heat, stirring occasionally, until reduced to 3 1/2 cups, about 30 minutes. Stir in the vinegar and season the mole with salt and pepper.
Preheat the oven to 350°. In a large skillet, heat the remaining 1 tablespoon of oil until shimmering. Season the short ribs all over with salt and pepper. Cook half of the ribs over moderately high heat, turning occasionally, until browned all over, about 10 minutes. Transfer to a small roasting pan. Pour off all but 2 tablespoons of fat from the skillet and repeat with the remaining ribs.
Spread 2 tablespoons of the mole on each rib and arrange bone side up in the roasting pan. Add the stock to the roasting pan and cover tightly with foil. Braise the ribs in the oven for about 3 hours and 30 minutes, until very tender. Transfer the ribs to a platter and serve, passing the remaining mole at the table.
Quinoa pilaf and roasted squash and root vegetables.