It is in fact almost impossible to cook Italian without the cipolla , or onion. Onions are the mainstay to the Italian soffritto, which is the basic seasoning ingredient for numerous sauces which also includes carrots, celery, and garlic, all saut ed in a little olive oil. This trilogy of vegetables lays the basic foundation for many recipes to which other ingredients are added. The onion family includes over 300 species, the most common ones being scallions, leeks, yellow onions, white onions, red onions, shallots and chives. These sweet onions are often named after where they are grown, such as Vidalia, or Maui onions.
Onions have been a Mediterranean staple from prehistory, although it's origins are purely Asian.
In Italy, they can be traced to recipes recorded as far back as the first century, with their importance to Italian cuisine growing from that point on. A strong onion scent generally means the onion has begun to deteriorate, or is bruised under the skin. Store these onions in a basket lined with paper towels in your refrigerator, or in a basket in a cool place with lots of air circulation. Trim back to 2 inches of green, and clean carefully as most leeks are generally full of grit. Simply slice down the center, fan open the leaves and hold over a running tap until all the grit has been removed.