Bolognese is a meat-based sauce from (as its name suggests) Bologna, Italy — but let’s be more specific.
A true bolognese is made with a blend of ground meat —mostly beef with some pork for fat and flavor; this distinguishes the sauce from other ragùs found across Italy. In Southern Italy, Neopolitan ragù is made with whole cuts of beef and pork are braised in the sauce, rather than using finely chopped or ground meat.Equally as important to the meat is the soffritto that creates the base of flavor for a traditional bolognese sauce. Start with roughly equal parts olive oil and chopped pancetta. Sauté the pancetta to render the fat, and then add your soffritto, which in this case includes onions, carrots, and celery (all finely chopped).
Next, add your beef, and brown for a minute or two before adding just a small amount of tomato paste and red or white wine, stirring well to combine. Allow the wine to cook off to prevent an unpleasant metallic taste.
However, the real secret to making bolognese (that so many people leave out) is the addition of milk, which should be added slowly to incorporate. While many claim the addition of milk keeps the meat tender, the milk more importantly provides a silky texture and the natural sugars from the milk improve the taste of the ragù.
Then, season your bolognese with salt and pepper, and cover while it cooks on low for three to four hours to meld the flavors.
Once it has finished cooking, serve with the traditional tagliatelle and grated Parmigiano-Reggiano.