31 Days of Vegetables

Onions: The Best Ways to Pick Them, Cook Them, and Eat Them

updated Jul 15, 2020
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Credit: Joe Lingeman/Kitchn; Food Stylist: CC Buckley/Kitchn

Do you think of an onion as a vegetable? You should! Onions are absolutely vegetables, and quite good for you so eat up. Here’s all you need to know about the most savory, useful, can’t-imagine-food-without-it vegetable of all: the humble, indispensable onion.

The Onion Top 5

Five must-reads for the allium-eaters among us.

  1. Is it safe to eat sprouted garlic and onions? (Short answer: Yes absolutely, although they may be slightly more bitter.)
  2. A new onion that won’t make you cry.
  3. Are pre-peeled onions worth the extra cost? A perspective.
  4. How to change the intensity of onions’ flavor in cooking.
  5. Bite-sized bloomin’ onions, wow!

Types of Onions

Onions are one of the most ancient vegetables around; they’ve been eaten for at least 5000 years and evidence has been found of cultivation over 7000 years ago. (Wikipedia)

When it comes to the most onions found in the grocery store, yellow onions are all-purpose and inexpensive, and slightly sweet. White onions are a little sharper and more pungent (they make me cry worse!). Sweet onions are even sweeter than yellow onions (and also more perishable). Red onions are relatively mild and really beautiful in salads and raw dishes. They turn pink and magenta when cooked.

Read more about the different types of common onions here:

Also, can you tell at a glance how many onions are in a pound? It’s usually about 2 medium onions:

Shallots vs. Onions

Shallots are a smaller variety of onion with a delicate, mild flavor. (Read more about shallots here.) They’re wonderful in dishes that call for raw onion or garlic, as their flavor isn’t as pungent and is a bit sweeter. You can swap onions and shallots, although keep in mind that an onion will be more pungent than a shallot.

Are Scallions the Same as Green Onions?

Yes! Scallions and green onions are very young, immature onions that haven’t fully formed a bulb. (When to use the white parts and green parts of a scallion.)

Spring onions, on the other hand, are a little more mature and potent in flavor, but still mildly than fully-grown onion bulbs.

Chives vs. Green Onions


Best Substitutes for Onion and Green Onions

No onions or green onions/scallions? Here are a few ideas for good substitutions:

How to Cut an Onion

Here’s one of the first things almost everyone should learn in the kitchen: How to slice and dice an onion! It’s a fine test and training ground for knife skills.

The Best Ways to Keep from Crying While Cutting Onions!

Onions have the power to make us all tear up while cutting them. I find that the best way to avoid this is to wear contacts while chopping through a bunch, but other than this, what have you found to work best in avoiding stinging, tearing eyes? Here are a few more ideas:


How to Caramelize Onions (and Freeze Them)

Once you know how to cut onions, one of the best things to learn next is how to caramelize onions. Cooking onions down into a sweet, savory, jammy concoction of caramelized strands is one of the kitchen’s greatest cooking magic tricks. Once you have caramelized onions you can put them in soups and stews, pile them on toast and butter, heap them on top of cooked meat.


  • Why You Should Freeze Caramelized Onions (and 3 Ways to Do It)

Onion Nutrition

One medium raw onion (100g or so) has about 40 calories and a modest amount of Vitamin C. It’s also a vegetable that has slightly higher amounts of sugar than some other veggies; it clocks in at about 4g of sugar (this still is low compared to pretty much any fruit). Overall onions are totally great part of a balanced diet and is just one more vegetable to help you eat your daily five servings.

The Best Way to Store Onions

Regular bulb onions can be stored on the countertop in a cool dry place for several weeks, or until you see signs of mold or wilting. Do keep potatoes and onions well-separated, as they foster faster spoilage in each other.

Green onions and spring onions can be left on the counter for a day or two but will stay fresher over the course of a week when stored in your crisper drawer.

Can Dogs Eat Onions?

Onions are not safe for dogs, according the American Kennel Club, and all forms of onion should be avoided — including and especially foods with onion and garlic powders. If your dog eats onion, call your veterinarian.

Can You Freeze Onions?

Onions lose their crisp texture and can get watery and mealy when frozen. However, if you know you’re just going to cook them, then it’s OK to freeze them. Also, as noted above, caramelized onions are fabulous frozen. Make a big batch in your slow cooker and freeze them in bags.

The Best Ways to Use Up Leftover Onions

Have leftover onions? Make sure to refrigerate any leftover cut-up onions (don’t leave on countertop). If you have leftover onion, caramelize it and freeze it!

Our Top 12 Onion Recipes

What’s your favorite recipe or use for onions? Any favorite way to cook it?

31 Days of Vegetables: How to fall in love with vegetables in 31 days. How many of these splendid veg have you eaten this month? Take a look at the whole list and take our July challenge to eat every single one!