How to Make It
Preheat the oven to 325°. Season the ribs with salt and pepper. In a large enameled cast-iron casserole, heat 1 tablespoon of the grapeseed oil. Add half of the ribs and cook over moderately high heat, turning occasionally, until browned all over, about 10 minutes. Transfer the ribs to a baking sheet. Repeat with the remaining 1 tablespoon of grapeseed oil and ribs.
Pour off all but 2 tablespoons of fat from the casserole. Add the apples, leeks, fennel, garlic, caraway and a generous pinch each of salt and pepper. Cook over moderate heat, stirring occasionally, until softened and just starting to brown, about 12 minutes. Stir in the flour and cook for 1 minute, then add the stock, beer, coffee, mustard, thyme and bay leaves and bring to a boil. Add the short ribs, cover and braise in the oven for about 2 hours and 30 minutes, until very tender. Let stand at room temperature for 1 hour.
Using a slotted spoon, transfer the short ribs to a platter and tent with foil. Strain the braising liquid through a fine sieve into a heatproof bowl, pressing on the solids; discard the solids. Skim the fat off the braising liquid.
Wipe out the casserole and melt the butter in it. Add the shallots and cook over moderate heat, stirring, until softened and browned, about 5 minutes. Add the sugar and cook until melted. Add the strained braising liquid and bring to a boil. Simmer over moderately high heat until reduced by one-third, about 7 minutes. Season the sauce with salt and pepper. Add the ribs to the sauce and simmer over moderate heat until heated through, about 3 minutes. Top with chopped parsley and serve with the polenta.