Northern Italy differs from the rest of the Peninsula in a number of ways. Most traditional North Italian recipes call for unsalted butter rather than olive oil, and though there are many kinds of stuffed pasta, except in Emilia Romagna and Liguria the flat and extruded forms that are so important further south are less important, giving way to polenta and risotto, and, in the winter, to rich, hearty soups.
The North, especially Piemonte and Emilia Romagna, has excellent cattle breeds suited to meat and milk production, and also excellent hogs; as a consequence beef, veal, and pork are the meats of choice, with lamb and other animals playing a lesser role. Cooking ranges from boiling and frying through slow braising and stewing, and in the latter cases northern cooks use much less tomato, preferring to use wine or broth as the liquid, and chopped herbs for flavor. The results can be extraordinarily elegant, and the same holds true for roasts, especially those that contain winter vegetable stuffings.
There is also an extraordinary variety of fish; Comacchio, south of the Po Delta, is renowned for its eels, while the Veneto’s coastal lowlands provide mussels and clams, and the lakes and waterways inland a tremendous variety of fresh water fish, in addition to ducks and other wild birds.