Real Food Right Now and How to Cook It: Onions

The Real Food Right Now team has the occasional meeting to discuss what Real Food will be on the editorial calendar for the next few months. On our last call, we collectively realized that we had never done a post on onions, which was unbelievable mostly because the depth and breadth of this series is getting seriously huge. How could we forget onions, the flavor cornerstone of just about every cuisine on this planet? (The poor homely onion, always the bridesmaid, never the bride.) Here is our homage to the onion, without which many of our favorite dishes would be boring, indeed.

A Brief History

Although the wild ancestor of onions seems to have disappeared, the consensus is that they originated somewhere in Central Asia. Onions have been cultivated for millennia, and the Oxford Companion to Food reports that the texts from the ancient Sumerian city of Ur mentions onions being grown as early as 2,100 BCE, and by ancient Egyptians as early as the first dynasty (around 3,200 BCE). They were also mentioned in ancient Vedic texts and in the Bible.

The lower classes in ancient Egypt, Greece and Rome ate onions in quantity, often raw, although there is speculation that ancient varietals of the bulbs were milder than some of the more pungent cultivars we enjoy today. Christopher Columbus is thought to have brought the onion to the West Indies when he returned on his second trip. From there, onions spread across both North and South America.

Factual Nibbles 

  • Onion skins were put over the eyes of some mummies from ancient Egypt, and evidence of onions placed in the pelvis, ears and torso of mummies has also been found. 
  • One of the world’s largest onions was grown in England, weighing in at a whopping 18 pounds. (I thought these photos of the bulb were fake at first, but no – read more about the couple who grew it in Lucky Peach’s look at the UK’s giant vegetable-growing subculture.)
  • There are a number of religious taboos against eating onions. Ancient Egyptian priests were forbidden from consuming the vegetable. In India, Brahmins, Jains and Hindu widows have traditionally shunned onions. (Here’s a fascinating piece from the New York Times on onions in Indian legend and popular politics if you want to learn more about onions on the Subcontinent.) 
  • By law, the trademarked “Vidalia” onion, a sweet variety, is grown only in parts of Georgia. Growing of the cultivar started in the 1930s in Vidalia, Georgia.
  • According to food scientist Harold McGee, onions take up sulfur from the soil to produce the various compounds that result in their distinctive peppery, pungent flavor. These compounds are stored in cells that, when ruptured (due to cutting or chewing), release their strong-smelling (and eye-irritating) molecules.


Allium cepa, the bulb onion, is in the Amaryllidaceae (Amaryllis) family, and counts as its cousins many lovely garden plants, including the eponymous amaryllis, along with daffodils, snowdrops, tuberose and a number of ornamental lilies. Aside from the bulbing onion, by far the most common species of Allium grown, genus also includes shallots, garlic, ramps and chives.

Bulbing onions are commonly divided into two different types:

  • “Dry” onions are harvested when their tops flop over. They are usually stored for longer use over the fall and winter months. Dry onions tend to have less water content and are “hotter” than green onions. They account for the majority of US onion production. Dry onions have to be dried (or “cured”) for a period of time to prevent rotting.
  • Green (aka “spring”) onions are harvested while the tops are still green. These onions are sometimes pulled before the bulbs have fully formed, to capitalize on their edible green tops. Later in the season, they are sold as “fresh market onions” with larger bulbs. Fresh market onions have higher water content and tend to be milder than dry onions.

Onions can be planted as “sets” (seedlings) or can be grown from seed. Globally, China, India, the US, Iran and Russia are the top dry onion growers. In the US, California, Washington State, Oregon and Idaho grow the most onions. Onions are pretty easy to grow at home on your counter – here’s a quick tutorial on how to grow onions from discarded onion bottoms.


Fresh market onions (aka, “Spring” and “green” onions) are available from March through August. Dry onions are available year round, as they can be stored for long periods of time in the right conditions.

Environmental Impact

Onions are a pretty water-intensive commercial crop, which makes them less than ideal if sourced from drought-impacted areas. (As an aside: onions that have been exposed to environmental stresses like drought tend to be far more pungent.) The good news is that you should be able to find onions – both the dry and spring types, depending on season – at just about any local farmers’ market, year round. Onions are also very susceptible to nematodes and other insect pests and to a number of different fungi that can cause the bulbs to rot. In addition, they don’t compete well with weeds. All of this adds up to a lot of likely pesticide use in conventionally grown onions, which make an appearance on the Environmental Working Group’s Shopper’s Guide to Pesticides in Produce at number 45. If all of this leaves you concerned, choose locally grown onions and talk to your local farmer about his or her growing practices.

Characteristics and What to Look for

Onions are divided into four major types based on their color and flavor: red, yellow, white and sweet. Red, yellow and white types are available as both spring and dry onions.

  • Red onions (aka purple onions) have reddish to purple skin and red-tinged interiors. They tend to be sweeter than either white or yellow onions and are often quite large. 
  • White onions (aka Bermuda onions) are more pungent than their yellow or red cousins. They are also a bit more tender than the other types.
  • Yellow onions (aka Spanish onions) are the most common types seen in grocery stores. They have yellowish, papery skin and a creamy white interior. Yellow onions are great all-purpose onions. 
  • Sweet onions are usually specially grown in certain parts of the country that have soil and climate that produces a mild, sweet type of onion. Examples are Vidalia and Walla Walla onions. They are far less sharp than the other types of onions.

For dry onions, avoid any mushy or brown spots, as these can cause the entire onion to rot quickly. Also choose onions that feel heavy for their size and are not sprouting. For fresh spring onions, look for glossy skin and, if their greens are still attached, perky, fresh green tops.

Nutrition and Effects on the Body

Onions are low in calories and high in fiber, and they are loaded with vitamin C. They’re also pretty good sources of vitamin B6, folate, potassium and manganese.

The pungent bulbs have been used since antiquity all over the world for a number of different ailments, from lung problems in India to snakebites in Medieval England (admittedly, neither “medicine” nor “science” were the strong points of medieval Europe). Recent research is shoring up some of the ancient beliefs about the physical benefits of onions (although they won’t protect you from snakebites. Probably.). Their high flavonoid and polyphenol concentrations have been linked to lowered risk of certain types of cancers and cardiovascular disease. Even more interesting, scientists have recently discovered that a 9th century treatment for eye infections using onions and garlic kills methicillin-resistant staphylococcus aureus (MRSA), so maybe ancient scientists were on to something, after all.

What to Do with It and Cooking

Onions are the true workhorses of the kitchen and are absolutely vital to most cuisines around the world. They are combined with carrots and celery as a flavor base in French and Italian cuisines (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. 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 the world’s best dip and in Mexico they are pickled and added to tacos.

I don’t get to eat onion-centric dishes as much as I’d like, because my husband is allergic, but one of my favorite onion dishes is the Alsace onion tart, made with lots of caramelized onions and heavy cream, and the other is French Onion Soup, which has a pretty interesting history all its own. Here’s a great roundup of 40 onion-centric recipes from Saveur.


Stored in a cool, dry place, dry onions keep for many, many months. (Exposing them to light hastens sprouting, which can mean quicker rotting.) Spring onions should be used within a week. Store them in the crisper drawer of your refrigerator.

Pro Tips

Chopping an onion properly is one of the first things I learned in culinary school – and it’s a good life skill for anyone who likes to cook. Here is the lovely Jaime Oliver walking you through how to chop an onion a few different ways. Here is a man who chops onions faster than a blender (just for your reference – do not try this at home!).

Surely, what you really want to know, though, is how to stop crying when you chop onions. There are a few different methods, ranging from the absurd to the sort-of plausible. Here is a highly scientific test of a few of these no-cry methods, with the winners being:

  • Wear goggles (they make silly onion goggles, but regular swim goggles will do) 
  • Cut the onion under a vented hood
  • Freeze the onion for a few minutes before chopping

Another pro tip – to get the onion-y funk off of your hands after you’ve chopped one up, rub your hands on something made out of stainless steel. (They even make a special stainless steel bar just for this purpose, but I find that rubbing my hands on my stainless kitchen sink is just as effective, although your family may give you the side-eye when you do it.)

Stretching Your Food Dollar Through Preservation

Onions can be turned into jam (like this bacon and onion jam or all of these onion jams). You can freeze fresh onions, or even smarter, freeze caramelized onions (here’s how to do it). 


Roasted Fresh Onions with Sage, Toasted Hazelnuts and Lemon

This is the perfect dish to make right before spring turns into summer: the weather is usually still cool enough to turn on the oven and fresh onions and sage are at the market. Serve these onions alongside a steak or grilled chicken or tofu, or cool and use as a topping for a fresh arugula salad.

If you can’t find fresh (spring) onions, substitute red onions – just be aware that red onions are often far larger than fresh onions, so adjust the recipe accordingly.

5-8 medium fresh (spring) onions, tops removed
10 large fresh sage leaves
Kosher salt and freshly ground pepper
Extra virgin olive oil
13 cup hazelnuts
Zest and juice from 12 lemon


  1. Preheat the oven to 400F.
  2. Quarter the onions through the root end, being sure to keep the quarters intact. In a medium bowl, toss the onion quarters and sage leaves with the kosher salt and pepper, and a liberal amount of extra virgin olive oil. Spread the mixture on a large, rimmed baking sheet. Roast until the onions begin to soften and brown and the sage gets crispy, about 20 minutes (or longer depending on the size of the onion quarters). 
  3. Meanwhile, toast the hazelnuts: place the hazelnuts on a small, rimmed baking sheet. Toast for about 10 minutes, or until the nuts are fragrant and golden brown. Remove from the oven, let cool for a few minutes, then rub the papery skins off with a dishtowel and discard. Roughly chop the hazelnuts and set aside.
  4. In a serving bowl, gently toss the roasted onions and any accumulated juices, sage leaves, chopped hazelnuts and lemon zest. Sprinkle with lemon juice and taste (and correct) for salt. Serve warm or at room temperature.

(*Real Food rule of thumb: We think that first and foremost, in terms of nutrition, people should eat lots of fruits and vegetables whether they are organic or not. The EWG’s guide is a handy list, but we will point out here that the impacts of pesticides are not limited to your ingestion of them – agricultural chemicals also affect farmworkers and local waterways, both good reasons to buy organic, even those vegetables that carry a light pesticide load. Also, it has been demonstrated that produce grown by small-scale farmers, even those who are not certified organic, tends to have a lighter pesticide load than its industrially-produced counterpart, owing to industry’s tendency toward large monocrops.)