I love love love me some caramelized onions and just about anything I can think of that can be made with them. I’m guessing you do, too, or you probably wouldn’t be here looking at this post, Caramelized Onions Three Ways. All of the recipes I use call for three to four pounds of onions, more on that below and all make absolutely stellar Caramelized Onions. If you want to make a smaller amount, you’ll probably want to use the Stovetop Method.
Let’s talk basics. The National Onion Association (I’ll cite NOA a couple of times in this post and you’ll see a couple of their charts) describes the process of caramelizing your onions:
About Caramelized Onions Three Ways:
Caramelized onions are so crazy good. The thing is they’re time-consuming, at least if you want onions with a deep rich flavor and just the perfect, tender bite. It’s gonna take a good amount of time and effort and maybe even a few tears! (Some great hints on that, below.)
Oh, you can probably knock off just a few, say for a quick burger topping in 30 to 35 minutes or so, but to make a larger quantity can be quite an undertaking. All three of the methods below help to shortcut the standard method of just standing at the stove and stirring.
And speaking of time, Tom Socca wrote an article for Slate, “Layers of Deceit” subtitled “Why do recipe writers lie and lie and lie about how long it takes to caramelize onions?” So he’s a little dramatic, but everything he says is so true!
Three Kinds of Caramelized Onions:
Bon Appetit talks about three different kinds of caramelized onions each one cooked to a different state. Personally, I don’t consider the lighter ones to be fully caramelized but do keep in mind that how caramelized your onions are is in your control. You can stop at any stage.
- Blonde: The onions are just starting to pick up color but will still according to Bon Appetit have a good amount of bite.
- Golden Brown: In this stage, most of the liquid is mostly gone and the onions are soft throughout and have picked up some good color.
- Deep Golden Brown: Taken to this stage, they are dark, jammy, and beautifully caramelized.
The Three Ways to Caramelize Onions:
I have three different ways to caramelize onions on my site! Each has advantages and drawbacks. I have been working on updating all these posts with step by step photos and text, so the recipes are there; the new look, improved posts will be coming soon.
All three are going to give you stellar caramelized onions. Here I’m talking about cooking time, not including the prep time for peeling and cutting and all recipes call for two to four pounds of onions, although I usually make four pounds at a time. More on that below under Big Batch:
- Stovetop: This method is mostly hands-off and can be done with more care and attention with two to three pounds of onions in about 50 minutes or done more easily and slowly in about 75 minutes Four pounds will take a little longer and fewer onions work, too, and take less time. You’ll find the method in my recipe for my Caramelized Onion Galette.
- Oven Method: This is Cook’s Illustrated Method and it involves a heavy, lidded Dutch oven and baking the onions, stirring now and then and then finishing them off on the stove. It takes about three hours total but most of that is while the onions are in the oven; actual working time is minimal but you do need to be on hand to stir a couple of times while they are in the oven and to finish them on the stove. This works well with a larger amount of onions and calls for four pounds. It will probably work with less but the timing will be off.
- Slow Cooker: the Slow Cooker Method is absolutely the easiest way to caramelize onions. Once they are totally softened, which takes hours and hours but can be done overnight, they can be finished off on the stove in 20 to 30 minutes. It’s the least investment of actual work time but the longest in total time. This works well with larger amounts, say three to four pounds, and can be made with even more onions, but that does add time.
The Best Onion to Use to Make Caramelized Onions:
First of all, for the easiest job, use large onions. That’s just because it will take much less time and effort to prep them. If you use small onions, you’ll lose so much when they’re trimmed and peeled that you might want to add additional onions to your recipe to make up for it.
Any onion will caramelize given enough time. Here are a few general things to consider:
- Onions that have more moisture will take longer, especially using the Slow Cooker method.
- Each variety of onion will have its own distinct and unique flavor.
The recommended type of onion to caramelize (according to the National Onion Association & Bon Appetit) is the common yellow onion. They caramelize beautifully and have a rich, savory flavor. There are many varieties, but we’ll see two main types here in the States at our grocery stores.
- Basic Yellow Onion: This onion is one you’ll find during the spring and summer. It has thin, almost delicate outer layers of papery skin and more moisture than the “storage onions” below. They’ll take a little longer to caramelize than the storage onions.
- Storage Onions: These onions are what you’ll find in the fall/winter seasons. They have more layers of outer skin and that skin is more substantial than the warmer season onions. They are the easiest onions to caramelize due to their lower moisture content. Bonus because so many recipes made using caramelized onions are cool-weather recipes.
All have higher moisture content and are sweeter than the common yellow onion. They will caramelize, but do so carefully; the additional moisture means longer cooking time and they can become mushy. A workaround is to cook until browned, drain off the juices, reduce the juices and then add the onions back in to finish and caramelize.
- Spanish Onions: These are a yellow onion but generally when they’re called “Spanish” they are often large, mild and a little sweeter than the basic yellow onion and that sweeter flavor does come through
- Sweet Onions: There are many varieties but you might recognize Vidalia, Maui and Walla Walla. The final caramelized onions will be distinctly sweet.
- White Onions: These have more of a bite and aren’t usually considered an ideal option to caramelize but they do have a more intense, almost spicy flavor once caramelized. These are probably best used as a topping rather than in a soup.
- Red Onions: The moisture content varies by season and they will caramelize into a dull burgundy color. They’re wonderful as marmalade or jam and I sometimes toss one into my yellow onions when I caramelize them.
- Leeks, Scallions & Shallots: While shallots will caramelize beautifully, I have only done so with a very small amount specific to a recipe; I have never caramelized Leeks or Scallions; I really don’t have any hands-on experience with doing so.
The Best Way to Cut Onions for Caramelized Onions:
Do yourself a favor and get large onions. Smaller onions will take more work to peel and you may need to add an onion or two to your batch to make up for the additional loss from peeling. If you have a scale use it, or weigh at the store when you buy, or estimate from the number of pounds in the bag. You will always want to cut pole to pole for the best texture, and all the recipes I use call for cutting 3/8ths of an inch thick.
If cutting by hand, sharpen your knife. A food processor will work but it’s nearly impossible to cut pole to pole and has to be constantly emptied as you work. Personally, just for quality, I’d cut by hand before using my food processor.
If you have a kitchen slicer, a cheapie runs about 30 to 35 bucks, use it and you can have pounds of onions sliced perfectly in minutes after you have them all peeled. How fast? Less than a minute a pound. Four pounds takes about three minutes.
- Skin all the onions at once and get rid of the skins or save them for stock; that means you won’t be picking out pieces of skin from the onions. The skins stick to them! Trim off both the root and stem end and skin by making a cut from one of those trimmed ends to the other right through the first layer of the onion skin, peel it and set the onion aside.
- Slice the onions pole to pole (that means cut from the root end to the stem end or visa versa) about 3/8ths of an inch thick. Cut your onion in half, lay them cut side down and angle your knife as you cut from one edge to the other; cut like you would cut apple wedges only thinner – aim for 3/8ths of an inch thick.
- Those thin pole to pole slices is what is going to be the start of onions that hold together in your soup (or any other recipe) and don’t disintegrate while at the same time will be absolutely tender with just the right consistency.
Using Caramelized Onions:
You are only limited by your imagination! Do try not to stand in front of the fridge just eating them by the forkful as I’ve heard some people say they do! And they are that good! They are your onions, though so if you must, lol.
- Soups: Make French Onion Soup or add a bit to add richness to other soups. A spoonful mixed in a Lentil soup can be fabulous.
- Use as a Topping: Serve over steaks, chops, burgers or sandwiches.
- Layer Them: Layer onto a pizza or in quesadillas, grilled cheese or BLTs.
- Mix Them: Mix into a compound butter, maybe with herbs, to melt over burgers or steaks, or mix into scrambled eggs or into sour cream for a dip. Use as a Flavoring Agent: They can be a flavoring agent for various pasta dishes, especially creamy ones, risotto or maybe other dishes.
- I’d love to hear how you use your caramelized onions!
Storing Your Caramelized Onions:
Caramelized onions may be stored in the refrigerator or the freezer.
- Refrigerator: The onions may be safely stored in the refrigerator for up to three to five days; many people use them for up to a week. Transfer to a clean container, don’t pack them in tightly, cover and refrigerate promptly.
- Freezer: The caramelized onions freeze well and hold up well when thawed, especially when they have been cut pole to pole.although they may give off some additional juices when thawed. Onions, frozen, will still be safe longer, for best quality, store in the freezer for no longer than six months.
Freezing: You may wish to freeze in several sizes according to your planned use for them in the future. Cool before freezing, label, and date the packages.
- Many people like to freeze in ice cube trays, pop the onions out and gang them up in a Ziploc. I find this fussy, it makes my trays smell and takes up too much room in the freezer. They can also stick together and are at risk for freezer burn.
- Some people like to line muffin tins and freeze in cup quantities then add to Ziploc bags. These have some of the same drawbacks as the ice-cube onions.
- I prefer freezing in various sizes in small, cheap sandwich bags. As each bag is filled, I roll it tightly, label it where it shows on the outside, freeze and then add the small rolls neatly into a larger Ziploc where they will stay together. The disadvantage is that more plastic is used but the advantage is the onions are protected by multiple layers and take up little room.
- In some recipes, you can just toss the onions in while still frozen.
- Thaw overnight in the refrigerator for the best onions.
- Run warm water over the onions in the package until warm enough to use.
- In a pinch, microwave for a minute or two.
- Toss into a saucepan and gently warm.
No More Tears When Cutting Onions:
According to the National Onion Board (I’ve spent a lot of time on their site!) When an onion is cut, sulfur compounds mix with alliinase enzymes, which irritates the eye and brings on the teary experience.
If you’d like to see a little more science and info about these methods, check out this paper from the University of Bristol on The Lachrymatory Factor in Onions. Greatist has also reviewed some of the methods below.
Here’s the bottom line on what works and what doesn’t to deduce tearing when cutting onions:
- NOA recommends you chill onions at least 30 minutes before cutting. Refrigeration will slow down the chemical reactions. Freezing works, too, but is hard on the onion and your hands.
- NOA also recommends a sharp, straight-edge knife to minimize damage to the onion cells, thus creating less of the
- NOA recommends, finally, to cut the root end of the onion last, as it generally has the highest concentration of tear-producing compounds. This is not really practical advice when cutting a lot of onions.
- Ventilation may help; be sure the ventilation isn’t pulling the air up from the onions past your face.
- Goggles or glasses can offer some protection if you’re very sensitive. And yes, there are even special onion goggles. It’s a thing.
- Cutting onions with a piece of bread in your mouth. Greatist feels this helps, possibly absorbing some of the compounds before they reach your eyes. I haven’t tried it but have visions of wet, drool sogged bread falling on my onions!
- Soaking in water or cutting underwater just makes the onions wet, slippery and dangerous to cut; soaking seems to have a minimal if any effect on the compounds.
- Microwaving turns out to be a crazy half baked (my bad) idea. The onions are slippery, hot, and just a mess, according to Greatist.
Going Big Batch:
I rarely caramelize a small number of onions unless I’m really pressed for time and some of the recipes on my site that use a smaller amount are actually made with a portion larger batches. Of course, I state so and direct you here or to one of my posts so you can do the same.
It does take more time to caramelize more onions but it maximizes your time and has a big payout! Just think: Onions for your recipe and more to use in something else or to freeze. To me, there’s no sense in spending 30 to 35 minutes caramelizing a few onions when I can literally do pounds of them in 15 to 20 minutes more on the stove or use one of the other, easier methods.
It also, obviously, takes more time to prep that many onions, so when I know I’ll be making a recipe that has caramelized onions, I usually plan ahead, buy more onions and make them a few days before I need them when I have the time.
I usually make four pounds of onions at a time which is enough for every recipe on my site (and most recipes for French Onion Soup, including my Guinness & Onion Soup) with extra caramelized onions. There is one exception: The Cook’s Illustrated French Onion Soup which calls for the full four pounds of onions.
Four pounds also is a great amount to fit in my Dutch oven and four pounds works well in my slow cooker, too. My standard slow cooker will hold more onions; four pounds take it about 2/3 full but it does increase the cooking time past where I’m comfortable, but that’s me. You do you.
Recipe Variations For Caramelized Onions:
Although I prefer to use olive oil, butter or a mix of both, some people caramelize onions dry, especially if they are using the Slow Cooker Method. I personally have never tried caramelizing onions with no fat at all.
You’ll see many additions to Caramelized Onions and none of them are necessary, although some enhance the onions:
- Sugar: White or brown sugar is sometimes used to promote quicker browning; usually a tablespoon. Onions have their own sweetness just as is, with no sugar needed, but when cooking a small amount, there is a difference in how quickly they color. One tablespoon in three or four pounds didn’t seem to make any difference I could see.
- Salt: You’ll sometimes see salt used in recipes; it’s a judgment call. Generally, there isn’t enough salt called for to draw a significant amount of moisture from the onions, only enough to flavor.
- Herbs: Usually thyme but sometimes rosemary or other herbs may be added.
- Garlic cloves: Just toss whole, peeled garlic cloves in. You can pull them out to use in different recipes (and freeze them coated in olive oil in small quantities) and they’ll flavor the onions, too, just a little, as they cook.
- Baking Soda: This is sometimes added. The rule of thumb is 1/8 teaspoon per pound of onions. The National Onion Association recently did a post on these Faster Caramelized Onions. They state the onions become soft and jammy, aren’t as dark and the pan is messy; adding a bit of water and stirring the residue in, then allowing it to evaporate would help with both.
I hope you found this information useful! I’d love to hear your comments; let me know if I’ve missed anything, what your experiences or fave tips or tricks are (do tell!!) and what works for you and doesn’t!! Comment below and please feel free to share on social media or link up!
Caramelized Onions Three Ways:
(Click the photos to go to the page)