Italian ragù alla bolognese is a slowly cooked meat-based 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.

[6] The earliest documented recipe for a ragù served with pasta dates back to the end of the 18th century in Imola, near Bologna, from Alberto Alvisi, cook of the local Cardinal[7] Barnaba Chiaramonti, later Pope Pius VII.

Artusi commented that the taste could be made even more pleasant by adding small pieces of dried mushroom, a few slices of truffle or chicken liver cooked with the meat and diced.

Similarly, both wine and milk appear today in the list of ingredients in many of the contemporary recipes, and beef has mostly displaced veal as the dominant meat.

Common sources of differences include which meats to use (beef, pork or veal) and their relative quantities, the possible inclusion of either cured meats or offal, which fats are used in the sauté phases (rendered pork fat, butter, olive or vegetable oil), what form of tomato is employed (fresh, canned or paste), the makeup of the cooking liquids (wine, milk, tomato juices or broth) and their specific sequence of addition.

[19] According to UK cookbook author and food writer Felicity Cloake, "The fact is that there is no definitive recipe for a Bolognese meat sauce, but to be worthy of the name, it should respect the traditions of the area",[18] a view that is consistent with that often expressed by the Italian Academy of Cuisine.

[14] Spaghetti bolognese, or shortened to "spag bol" in the UK and Australia, is a popular pasta dish outside Italy, although not part of Italian cuisine.

The origins of the dish are unclear, but it may have evolved in the context of early 20th-century emigration of southern Italians to the Americas (particularly the United States) as a sort of fusion influenced by the tomato-rich style of Neapolitan ragù or it may have developed in immigrant restaurants in Britain in the post-war era.

The latter were in fact already widespread in the United States, unlike tagliatelle, traditionally made fresh and difficult to export due to the fragility of their consistency.