Soffritto

Soffritto (literally "sub-fried" or "under-fried"in Italian because it simmers in an emulsion of oil and very little water rather than really frying) forms the base of many common Italian dishes. It typically consists of aromatic ingredients sautéed with cooking oil. The basic Southern Italian soffritto is prepared with olive oil, chopped onions (or scallions) and sometimes chopped garlic cloves. In Northern Italy the most common soffritto is made with minced celery, carrot and onion.
While olive oil is most typical of much traditional Italian cuisine some regional recipes may call for butter as the main cooking fat of a soffritto (especially in Piedmont. which borders France and is influenced by French cuisine), but also in other parts of Northern Italy like Lombardy and the Veneto, which were historically occupied by Germanic and Northern peoples. In Northern Italy the cooking fat may also be corn or seed oil or even lard.
The next step is to add extra ingredients to the soffritto. There is a great variety of options, such as vegetables (carrots, celery, artichokes, etc.), mushrooms, pancetta , prosciutto, tuna, olives and so on depending on the recipe.

ee also

*Sofrito
*Mirepoix