Braised oxtail refers to a cooking method that involves slow-cooking the tail of a cow cut into pieces, in a flavorful liquid until it becomes tender and succulent. The term braise is used to describe a cooking technique that combines both dry and moist heat. Pieces are first seared in a hot pan or pot to develop a rich, browned exterior. Then they are placed in a cooking vessel (usually a Dutch oven) along with aromatic ingredients, onions and herbs.