Cut and trim the oxtails. Wash with water and vinegar. Combine the garlic, scallions, fresh thyme, onion, tomato, cilantro and some salt and pepper in a food processor or blender. Rub the paste into the oxtails and marinate overnight in the refrigerator. Place the oxtails into a pressure cooker and cook according to manufacturer's directions until the meat is almost falling off the bones, 45 to 60 minutes. Heat the oil in a heavy skillet. Add the sugar and let it melt until it gets to a brilliant brown color. Add the oxtails to the skillet (be careful, the sugar may splatter). Let it cook for another 20 minutes. Taste for salt. Serve with red beans and rice or over white rice.
Professional Recipe: This recipe was provided by a chef, restaurant or culinary professional and makes a large quantity. The Food Network Kitchens chefs have not tested this recipe in the proportions indicated and therefore cannot make any representation as to the results.