Caramelized Onions are one of the most delicious toppings for sandwiches, burgers, and so many various appetizers. While there are plenty of ways to over or under cook them, true Caramelized Onions are slowly and carefully cooked. That way, the natural sweetness of the onions and that signature caramel color develop the best flavor possible.
How to Make Caramelized Onions
Let’s start right at the top with the most important piece of information you can know about making caramelized onions – it will take time! The key to making the best, sweet and slightly nutty Caramelized Onions is cooking them SLOWLY! While I typically like a good shortcut, there’s no way to cut down on time here.
If you try to raise the heat while cooking your onions, you’ll just end up searing them instead of caramelizing them!
With all of that being said, taking your time and making real Caramelized Onions is so very worth your patience. There is an endless list of appetizers, sides, and entrees that all greatly benefit from the addition of perfectly soft, sweet, and caramel colored onions! This is one of those baseline recipes that every restaurant and home chef should master and always be ready to whip up. It’s one of those basics that just makes everything better when you can make it just right.
Similarly to roasted garlic, Caramelized Onions add something special to everything they’re served with! They add a rich flavor that’s both savory and sweet, and the consistency is soft and smooth, which is usually a nice contrast to whatever they’re paired with. The main reason you want to really take your time when making Caramelized Onions is because if you try to rush the process and sear the onions, you take away from all that’s delicious about them.
How to Make Caramelized Onions
Ingredients You’ll Need:
- Yellow Onion – stick to yellow onion or Vidalia onion.
- Olive Oil – Use a good quality olive oil.
- Sugar – A light sprinkle of white granulated sugar helps the process of caramelization by brining out more natural juices and sweetness of the onions.
- Butter – Butter is an optional ingredient, but I find that it helps to keep the onions from drying out.
- Deglazing Liquid – You can use water, broth, or white wine to deglaze your pan. It all depends on what flavor you’d like to be lent to your onions.
Prepare the onions.
Cut the onions in half first, then cut off the tip, peel the outer skin off, and slice the onion in thin strips to the root.
Cook the onions.
Add oil to a pan preheated at medium heat. To the pan, add your onions, salt, and sugar. Mix everything together so that the onions are coated with both the salt and sugar as well as the oil.
Lower the heat to medium low. Stir the onions every 5-10 minutes as they cook. They’re going to look white for a while – this is to be expected, so don’t worry! As they slowly cook, they’ll release liquids and turn golden brown after that.
Deglaze the pan.
The sugary liquids from the onions will likely settle on the pan, but this also depends on what kind of pan you’re using. To deglaze, simply scrape the pan as you deglaze it with a splash of liquid of your choice. (Water, broth, and white wine all work well.)
The total cook time for your Caramelized Onions will be around 45 minutes to an hour. Stir the onions from time to time, deglaze and add butter as needed, and don’t increase the temperature. Then, once they’re soft, golden brown, and fully caramelized… Enjoy!
Frequently Asked Questions
How to Serve Caramelized Onions
The possibilities here are truly limitless. Just to name a few serving suggestions:
Sandwiches, hot dogs, sliders, and grilled cheese.
In dips (think French Onion Dip and more)
Mixed with pasta and casseroles,
On top of nachos, tacos, and crostini
How much Caramelized Onions will I get?
Onions, much like many other vegetables that are mostly composed of liquid, shrink down significantly after cooking. So the 1 pound (or 2 large onions) you cook will only give you approximately 1/2 cup of caramelized onions.
Tips for the Best Caramelized Onions
- Use a large pan because you will need a good amount of space until the onions shrink down.
- Do not raise the heat! Cook the onions over medium low heat for the duration of the cook time.
- Stir often, every 5-10 minutes, to make sure all of the onions cook evenly.
- Keep cooking until the onions turn a deep caramel color. Don’t quit until you’re all the way done!
- If the onions and the pan look a little dry while cooking, add some butter.
- Depending on the pan you’re using, the sugary liquids that cook out of the onions can settle on the pan. Simply scrape the pan as you deglaze it with a little liquid.
Store Caramelized Onions in the refrigerator, in an airtight food storage container. Properly stored, they should stay good for up to a week.
You can always make a bigger batch and freeze them! Make sure to cool the onions completely before freezing them, then portion them into ice cube trays or a muffin pan (try using silicone muffin pan or line it with parchment paper). Set a timer and freeze them for 2-3 hours, then pop the frozen onion “cubes” into a freezer zip-top bag. Freeze it for up to 3 months.
- 1 lb yellow onion
- 1-2 tbsp olive oil
- 1 tsp coarse salt
- 1/2 tsp white granulated sugar
- 1 tbsp butter optional
- 2-4 tbsp deglazing liquid such as water, broth, or white wine if needed
- Cut the onions in half, through the root end to the top. Cut off the tip, peel the outer skin, and slice onion thinly to the root. Discard the tip and the root.
- Heat up a cooking pan over medium heat and add oil. Add sliced onions and season with salt and a little sugar. Mix onions to evenly coat them with oil and seasoning. Lower the heat a little and cook onions over medium-low heat.
- Stir onions every 5-10 minutes as they cook. The onions will look white for a while, they will release liquid and cook down slowly and will start to get golden and brown after that.
- Depending on the pan you're using, the sugary liquids that cook out of the onions can settle on the pan. Simply scrape the pan as you deglaze it with a little liquid. (Choice for liquid can be water, broth, or wine.)
- The total time will take 45-60 minutes. Make sure to stir from time to time as onions are cooking and caramelizing. Don't try to rush it or raise the heat because the onions will sear instead of caramelizing. Wait for them to naturally caramelize and brown.When onions are almost done, add a little butter and stir it in.