Bolognese sauce (known in Italian as ragù alla bolognese, ragù bolognese, or simply ragù) is a meat-based sauce in Italian cuisine, typical of the city of Bologna. It is customarily used to dress tagliatelle al ragù and to prepare lasagne alla bolognese. In the absence of tagliatelle, it can also be used with other broad, flat pasta shapes, such as pappardelle or fettuccine. Genuine ragù alla bolognese is a slowly cooked sauce, and its preparation involves several techniques, including sweating, sautéing and braising. Ingredients include a characteristic soffritto of onion, celery and carrot, different types of minced or finely chopped beef, often alongside small amounts of fatty pork. White wine, milk, and a small amount of tomato concentrate or tomatoes are added, and the dish is then gently simmered at length to produce a thick sauce. Outside Italy, the phrase "Bolognese sauce" often refers to a tomato-based sauce to which minced beef (or pork) has been added; such sauces typically bear less resemblance to ragù alla bolognese being more similar in fact to the ragù alla napoletana from the tomato-rich south of the country. Although in Italy ragù is not traditionally used with spaghetti, so-called "spaghetti bolognese" has become a popular dish in many other parts of the world.