These bittersweet bulbs of the grape hyacinth taste and look like small onions, which is why they're also called wild onions. Fresh cipollini are hard to find in the United States but do make an appearance in some Italian markets during the fall. Jars of cipollini preserved in oil are also sometimes available. For peak flavor, fresh cipollini should be slowly simmered or braised. They can be served as an appetizer or vegetable.