Fresh (or "spring") onions are freshly harvested, mellower and sweeter than cured storage onions.
Fresh onions will keep in a bag in your fridge for 1-2 weeks.
Onions are vital to most cuisines around the world. They are combined with carrots and celery as a flavor base in French and Italian cuisines, something called mirepoix in French and soffritto in Italian. And with bell pepper and garlic, and other aromatics, depending on the cuisine, to make the Spanish, Caribbean and Portuguese flavor base sofrito. Used raw, they add a crunchy, potent punch to salads, sandwiches and dips. When we eat them raw, we like to take out the bitterness with this technique. Cooked, they become meaty, rich-flavored and full of umami — especially if they are cooked low and slow until their sugars caramelize. Here’s how to caramelize onions. In India, onions are turned into pungent chutneys, in the US they are combined with sour cream to make a creamy dip , in Mexico they are pickled and added to tacos, and in Peru they are used in the famous salsa criolla or onion salad that is the base for their world famous ceviche.