Onion

Onion is a versatile vegetable that forms the foundation of countless dishes across various cuisines. While onions are available year-round due to storage and global cultivation, they are typically harvested in late summer through the fall. Onions are essential in many culinary traditions, including French, Indian, and Chinese cooking, where they are prized for their ability to add depth and sweetness when cooked, and a sharp, astringent flavor when raw. They can be caramelized, pickled, roasted, fried, or used raw in salads and salsas.

Onion Synonyms

Bulb onion
common onion
garden onion

Different Forms/Types of Onion

Frozen

Onions can be found frozen, either chopped or whole, which can be a convenient option for long-term storage without significant loss of flavor.

Pickled

Onions are also available in pickled form, which can be used as a condiment or to add a tangy flavor to dishes.

Caramelized

Some stores offer pre-caramelized onions, which are onions that have been slowly cooked down to bring out their natural sweetness.

Fresh bulbs

Onions are available as fresh bulbs, which are the most common form. They come in a variety of types, including yellow, red, white, and sweet onions, each with its own flavor profile suitable for different dishes.

Chopped/Sliced

Pre-chopped or sliced onions are available in the refrigerated section of many grocery stores, offering convenience for cooks who want to save time.

Dried/Dehydrated

Dried or dehydrated onions come in forms such as flakes, powder, or granules and are used for seasoning.

How to Choose Onion

When selecting fresh onions, look for ones that are firm and heavy for their size with dry, papery skins. They should have no soft spots, moisture, or dark patches. Avoid onions with sprouts or a strong odor as this indicates they are past their prime. For processed forms like frozen or dried onions, check the packaging for any signs of freezer burn or moisture, which can affect quality.

Cooking/Prep Tips for Onion

Onions are a foundational ingredient in many cuisines, offering a range of flavors from sweet to sharp depending on how they are cooked. For intermediate and expert home cooks, it's important to understand that the longer onions are cooked, the sweeter they become due to the caramelization of natural sugars. High heat cooking will brown onions quickly, providing a rich, savory flavor, while slow cooking will yield a sweeter, more mellow taste. When dicing onions, use a sharp knife to minimize tearing, and consider the size of the cut based on how quickly you want the onion to cook and integrate into the dish. For a more nuanced flavor, you can sweat onions over low heat to soften them without browning, which is ideal for dishes where a more subtle onion flavor is desired.

Shelf Life of Onion

Store whole fresh onions in a cool, dry, well-ventilated place away from sunlight. Do not store them in plastic bags as this can retain moisture and cause them to spoil. Chopped or sliced fresh onions should be stored in a sealed container in the refrigerator and used within a few days. Frozen onions should be kept in the freezer and used before the date indicated on the package. Dried onions should be stored in a cool, dry place in a tightly sealed container. Pickled onions should be kept in their original brine in the refrigerator once opened and typically last for several months.

Recommended Brands for Onion

dried onions: McCormick or Badia

fresh onions: No specific brand recommendation as fresh onions are typically not branded and quality can be assessed visually.

frozen onions: Birds Eye or Cascadian Farm Organic

pickled onions: B&G or Mrs. Fanning's

Cooking Techniques for Onion

Grilling: Grilling onions brings out their natural sweetness and adds a smoky flavor. Slice onions into thick rings or wedges, brush with oil, and grill over medium-high heat until they have char marks and are tender.

Sautéing: Quickly cooking diced or sliced onions in oil or butter over medium-high heat until they are translucent and tender is a fundamental technique. This method is often the first step in recipes to build a flavor base.

Caramelizing: Caramelizing onions over low to medium heat draws out their natural sugars and results in a deep golden brown color and sweet flavor. This process can take 30 minutes to an hour and is essential for dishes like French onion soup.