How To Make Caramelized Onions

October 13th, 2011 at 1:01 pm

Every time I make caramelized onions, I’m amazed at how such a simple cooking process can yield such a sweet, silky result. Caramelization is nothing more than the process of cooking something long enough to bring out and develop its natural sugars.

Inexpensive and easy to store, onions are a kitchen staple for me, especially in the fall and winter. Once caramelized, the options of incorporating them into your recipes are almost limitless.

  • Toss caramelized onions with sauteed kale, garlic, and brown rice noodles for a nutritious pasta dish.
  • Make a ginormous batch of caramelized onions (5 onions at least), then toss in some cooked chicken and broth to make a quick “French Onion Chicken Soup.”
  • Top roasted chicken or turkey with caramelized onions and toasted pine nuts.
  • Puree caramelized onions with chickpeas and olive oil for an easy dip.

Anyone can make caramelized onions. Below I’ll show you how. But first, a quick note about the photos.

It turns out that caramelized onions aren’t the most photogenic vegetable (especially when you’re snapping pictures in dim late afternoon lighting). Even in person, they’re kind of one of those ugly foods that taste delicious. So don’t let the photos fool you! Make these, even though they don’t have a ton of visual appeal. The natural sweetness and buttery texture will blow you away.

Start by cutting off the root and stem ends of some yellow or white onions, then slicing them in half lengthwise. Peel off the skin and cut the onions crosswise into 1/4-inch thick half moons. I would recommend caramelizing at least 2 large onions, because they really shrink down as they cook. If you want enough for soup or pasta, go with 4 to 5.

Heat up some olive oil over medium heat (I use about 1 tablespoon per onion) in the bottom of a large skillet or saute pan. This is key. If you use a high-sided pot, you’ll trap too much steam in with the onions and they won’t brown up and become sugary-sweet as quickly. Exposing them to a large heat surface area is important.

Drop in a few onion pieces after the oil has been heating up for a bit. When the onions sizzle, add the rest of them to the pan. Stir to coat them with the oil. They’ll look like this:

After about 10 minutes of cooking—stirring occasionally—over medium heat, season the onions with a few big pinches of sea salt. The salt will bring out more liquids from the onions and continue to move the caramelization process along. After 10 minutes of cooking, your onions will probably look something like these:

Reduce the heat to medium-low. Now you’re just going to cook the onions low and slow until they reach your desired shade of brown. As the pan dries out and the onions stick to it, add splashes of water. (I like my onions to be moist and silky, so I add at least a cup throughout the entire process of cooking 2 to 3 onions.) Don’t worry about the water diluting the sweetness of the onions. It doesn’t.

I usually cook my onions to a golden brown stage (which takes 25-30 minutes), so that they’re not too deeply hued to taste bitter but are definitely still caramelized. After the initial 10 minutes of cooking plus the additional 25-30 minutes, the onions will look something like these:

Storing & Using

If you’re going to use your onions right away, feel free to jazz them up a bit by tossing in some finely chopped fresh herbs (thyme and rosemary are delicious) or freshly grated nutmeg.

Caramelized onions also freeze well. Because they are already super soft and essentially “overcooked,” you don’t have to worry about them becoming too mushy in the freezer. Reheat frozen or refrigerated caramelized onions in a pot with a few splashes of water.

Do you have a favorite way to use caramelized onions? Please share in the comments.


Other News

I have a few fun events lined up this fall that I wanted to let you know about if you’re local:

  • On Monday, October 18, I’ll be teaching a cooking class at Willy Street Co-op West in Middleton from 6-8 pm. We’ll be making a gluten-free autumn feast, featuring Kale & Cranberry Salad, Chicken Strips with Maple Mustard Dipper, Spiced Quinoa & Vegetable Pilaf, and a fun twist on pumpkin pie. Call Willy Street or stop by the store to sign up!
  • On Thursday, October 20, swing by Eco-Fusion Design in Madison between 5-7 pm for an evening of tasty bites from my book, featuring Vom Fass gourmet oils and vinegars. Books will be for sale at the event and I’ll be there to sign them and chat with you about healthy gluten-free eating. You’ll also find plenty of unique ideas for eco-friendly home decor in the store.
  • On November 4 and 5 (Friday and Saturday), I’ll be at La Bella Vita’s gallery night and holiday open house with samples of recipes from my book. Books will be available for purchase at this event as well.



  1. I never knew you could freeze them – great tip!

  2. I adore caramelized onions… they make a great side when there are few veggies in the fridge… I actually start my frittata’s with them (make onions then pour egg over and put under the broiler) – a super fast and inexpensive meal that always seems to be a hit. Grazie mille! Claudine

  3. I’m not a fan of onions but the husband is. You make this look so easy I think I might surprise him with some homemade onion soup. Who knows, maybe the caramelized onions will win me over :)

  4. I made the “Best Ever Gluten and Dairy Free French Onion Dip Recipe” from The Whole Gang. This was my first try at caramelizing onions. What an easy process! Everyone enjoyed the dip so much I had to make more the very next day! It was exciting to finally find a dip that I can eat and those who don’t have food allergies truly loved! Thanks for showing how to caramelize them with detailed pictures and directions. This helps tremendously!

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