A Step-by-step Guide for Cooking Caramelized Onions
If there’s one thing in life that’s worth the wait, it’s caramelized onions. They’re easy, therapeutic to make (in my opinion), and absolutely delicious once they’re done cooking. Here is a step-by-step guide (with photos!) to help you make your own caramelized onions at home.
step one : pick your onion.
Yellow or white onions are the optimal choice here, as they have a lower water content so they’ll caramelize beautifully and a bit faster than sweet onions. Sweet onions do contain a higher water content, so they will take longer to caramelize. Red onions can also be an option, but their higher sugar content can make them more prone to burning, so keep a close eye on them. So to start, grab a large (go for the biggest one!) yellow or white onion.
step two : prep your onion.
First, cut the ends off of the onion.
Next, stand the onion up on one flat end, then carefully slice it in half lengthwise.
See how the onion has subtle lines that run the length of it? Those are important! The natural lines of the onion should be vertical as it stands on its end, so you’re slicing with the lines when you cut it in half.
Once the onion is sliced in half, peel off the crunchy outer shell and the outermost layer.
Lay the onions, cut side down, onto the cutting board.
step three : slice your onion into half moons.
Cut with the natural lines of the onion, and slice the onions halves into half moons. Make your onion slices about 1/8 of an inch thick, so they caramelize evenly.
step four : prepare the pan.
Heat a sauté pan with a large surface over medium heat. (You want as many of the onion slices to touch the heat as possible, to also encourage even caramelization). Add unsalted butter and olive oil, and allow them to melt and mix together. A good ratio to follow is one tablespoon of each for every pound of onion. Wait until the oil and butter are hot before adding the onion slices to the pan.
step five : separate the onion slices, and add them to the pan.
Avoid clumps of onion slices, and separate them with your fingers so they cook evenly. The best way to do this is by picking up the slices after you cut them, then gently separating them into a large bowl. That way, you can carefully transfer them to the hot pan.
step six : coat the onions and add a pinch of salt.
Use a wooden spoon or a wooden spatula to stir the onions around the pan, coating each of the slices in the oil and butter. Sprinkle a teaspoon of kosher salt over the onion slices, and stir to spread it throughout the onion slices.
step seven : patience.
Now we wait. 🙂 Let the onions do their thing over medium heat for at least ten minutes. After ten minutes is up, gently stir them around the pan, and turn the heat down to medium-low for the remainder of the cooking time.
From here, stir the onions every ten to fifteen minutes to encourage even caramelization, and keep an eye on their changing color so you can start to recognize the different color and texture as they caramelize. This entire process should take about 30-40 minutes, and you’ll know the onions are done once they’re very soft and much darker in color!
step eight : the finishing touches.
Almost there! After about 35-40 minutes, they onions will nearly be done. Once you get to this stage, add a tablespoon of aged sherry vinegar, and about a half teaspoon of freshly cracked black pepper. [ PLEASE NOTE : this is entirely optional! The onions will still be delicious if you do not add sherry vinegar and pepper. ] If you choose to not add these last two ingredients, simply cook the onions for another five minutes until they are deeply golden brown and very soft.
If you DO choose to add sherry vinegar and pepper, stir to coat the onions in both, and allow them to cook for about five more minutes to cook out the acidic flavor of the vinegar.
Remove the onions from the heat, and allow them to cool for about fifteen minutes before transferring them to an airtight container.
step nine : eat your caramelized onions on everything.
Scrambled eggs, tomato soup, grilled cheese, and avocado toast are all awesome vehicles for caramelized onions. You could also mix them into pastas, toss them into salads, or whatever else sounds good to you!
step ten : store your caramelized onions.
As long as they are in an airtight container in the refrigerator, they will keep for up to four days. I recommend freezing them though, as they’ll last up to three months this way. Spoon the onions into an ice tray to create small portions of them, then pop them into the freezer. Once they’re frozen, pop them out of the ice tray, and transfer them into a plastic freezer bag. Pop out a cube of frozen onions whenever you need to use them!
I hope this helps you feel comfortable caramelizing your own onions at home! If you ever have any questions, feel free to reach out to me. Also, tag me on Instagram if you get the chance to try these out! <3
how to make caramelized onions (step-by-step)
Ingredients
- 1 large yellow or white onion
- 1 Tbsp. unsalted butter
- 1 Tbsp. olive oil
- 1 tsp. kosher salt
- 1 Tbsp. aged sherry vinegar optional
- 1/2 tsp. freshly cracked black pepper optional
- time + patience
Instructions
- Cut both ends off of the onion. (Root and top). Cut the onion in half lengthwise.
- Peel the onion halves from their shell and outermost layer, then lay cut side down onto a cutting board.
- Thinly slice the onions into 1/8" slices, cutting with the natural lines of the onions to create half moons.
- Heat a pan over medium heat. Add olive oil and butter, and allow to melt and completely heat through.
- Scatter the onion slices into the pan, and toss to coat the onions in the butter and olive oil. Sprinkle the onions with kosher salt, then stir to coat the slices in salt.
- Allow to cook for ten minutes at medium heat. Stir to redistribute the onions, and turn the heat to medium-low.
- Stir every ten to fifteen minutes to encourage even caramelization, for a total of about thirty to forty minutes.
- (OPTIONAL) Once the onions are almost entirely browned, add the sherry vinegar and freshly cracked black pepper. Stir to mix into the onions, and allow to cook an additional five minutes.
- Remove the onions from the heat, and allow them to cool for about fifteen minutes before transferring them to a lidded container.
- Store for up to four days in the refrigerator, or freeze for up to three months.
Nutrition
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Comments & Reviews
I love caramelized onions but cook them slightly differently. Need to try your way. They look so good. Pinning for later!
I hope you get to try them this way, Jacqueline! I’m making some right now and my kitchen smells heavenly!
I love caramelized onions! We must have been on the same wavelength as I just finished making some for a chicken dish I created. They are the best thing since sliced bread! Your description of how to do it was so clear that I think anyone can do it. And I definitely think they are worth the wait. Yum!
Thank you so much, Linda! And great minds think alike! 😀 They are so worth the wait, especially since there’s so much “hands off” time. Plus, the versatility of caramelized onions never ceases to amaze me!
Caramelized onions are such a great topping for so many things. It’s a good idea to learn how to make them properly and your guide is perfect. I sometimes add a little brown sugar to mine at the end of cooking which adds a tad more sweetness to them.
I love the idea of adding brown sugar! That would be so good on top of burgers with some blue cheese! I’m drooling just thinking about it.
I love that you put these in the freezer — what a brilliant idea! Caramelized onions add such a wonderful flavor to so many dishes, but they take a little too long for quick weeknight dinners. I’m going to start making big batches and freezing them!
Caramelized onions are SO good, but they do take a long time! It’s so ideal to freeze them and use them as you wish! You’re right …they add such a wonderful flavor to so many things!
Got to love step 9!!!! This tutorial is so great. Makes me realize how incredibly simple these really are to make. Even I can do it!
It just takes some time, but you can DEFINITELY do it!
Your photos are gorgeous! I love carmelized onions so this post is very informative!
Thank you so much, Nicole! I’m so glad you found it to be helpful!
Worked out great!! I tried caramelized onions before. Your recipe was easy to follow we loved them
That’s awesome, Tatiana!! I’m so glad they worked out for you! They’re sooo good. Hopefully you can keep the recipe in your back pocket for more uses down the road!
I feel like I have been making them wrong all these years. Thanks for the step by step!!
Yummy! I love caramelized onions. There are so many dishes you can pair with these. I’m thinking about some on a cheeseburger right now!
Caramelized onions are magical! You’re reminding me that I need to make a new batch!
Such a great step by step! Patience is key with caramelized onions and I love the way yours turned out! Such a lovely golden colour. And a delicious addition to so many other recipes! (I’m thinking the top of my burger this evening!)
Burger topping is an AWESOME option, for sure! And thank you for the kind comment! Patience is definitely key with these guys, but the result is soooo worth it!
Caramelized onions are such a good addition to any savory dish, it’s great to make them and just have them in the fridge read to go, This recipe has such great photos of the process, it’s easy to visualized the well detailed instructions!
Thank you so much, Lauren! I wanted to make it as approachable as possible … I used to be SUPER intimidated by making them, but after a couple of times, I realized there was no reason to be! I love keeping these in the refrigerator for eggs in the morning, sandwiches / burgers at lunch, or chicken at dinner. They’re so versatile!