Onions are strongly flavored, aromatic members of the lily family. Most have edible grasslike or tubular leaves. Almost every culture  incorporates them into its cuisine as a vegetable and for flavoring.

Common or bulb onions (Fr. Oignons) may be white, yellow or  red (purple). Medium-sized yellow and white onions are the most strongly flavored.  Larger onions tend to be sweeter and milder. Widely used as a flavoring  ingredient, onions are indispensable in mirepoix (for making stock). Onions are also prepared as a side dish by deep-frying, roasting, grilling, steaming or boiling.

Pearl onions are small, about ½ inch in diameter, with yellow or white skins. They have a mild flavor and can be grilled, boiled, roasted or sautéed whole as a side dish, or used in soups or stews.

Choose onions that are firm, dry and feel heavy. The outer skins should be dry and brittle. Avoid onions that have begun to sprout. They should be stored in a cool, dry, well-ventilated area. Do not refrigerate onions until they are cut. Onions are available all year.

Why, again, do onions make us cry?   The process goes as follows:

Lachrymatory-factor  synthase is released into the air when we cut an onion.

The synthase enzyme converts the sulfoxides (amino acids) of the onion into
sulfenic acid.

The unstable sulfenic acid rearranges itself into syn-ropanethial-S-oxide.

Syn-propanethial-S-oxide gets into the air and comes in contact with our eyes.

The lachrymal glands become irritated and produces the tears!