Introduction: How to Caramelize Onions

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Caramelized onions are something I don't make very often because they take forever, but they really are worth it if you've got the time! I like making true caramelized onions - no sugar or vinegar here! Just lovely onion flavor.

You're looking at 45-60 minutes of cook time, so I normally try to multitask and cook other things - that way I'm in the kitchen to keep an eye on the caramelized onions but I'm not bored. :D

(Yesterday I made two cakes and some buttercream while the onions were going - you really do have time to make a lot!)

P.S. There are tons of tricks for cooking caramelized onions more quickly and efficiently, but I've never found them particularly useful. Many of them change the texture of the onions, so be warned! But if you feel like experimenting, check out this awesome write up over at Serious Eats.

Step 1: What You'll Need:

  • several onions - any color you like!
  • olive oil or butter (or both!)
  • salt
  • water
  • a good heavy pan, I prefer stainless or cast iron - non-stick is not ideal.

I prefer to use a mix of yellow and white onions, but you can really use whatever you like!

The reason I say that you shouldn't use non-stick is because you really do want the onions to get a bit stuck to the pan so you get those lovely little brown bits to scrape up. This is similar to the pan I use at home - it's a workhorse! Great all around, but especially for caramelized onions, tomato sauces and pan frying. :)

Step 2: Slice the Onions

I prefer to slice the onions across the grain (from root to tip) instead of with it for caramelized onions - it makes the slices a little fatter so they can better stand the heat. :)

But you can also do this part however you like - just make sure they're fairly similar in size and not too skinny!

Step 3: Heat Up Your Skillet and Add Your Fats

I like to do half and half olive oil and butter. For five onions, I'm using about 2 tablespoons of oil and 2 tablespoons of unsalted butter.

Place the skillet over medium heat and melt the fats together.

Step 4: Add in the Onions + a Few Pinches of Salt

Add the onions in and toss them around so every onion is coated in fat. If they don't look glossy, you'll need to add a little more fat. If the onions are dry, they will be more likely to burn and stick to the pan.

Once that's done, you can add the salt!

Salt is my secret for great caramelized onions. I do 2-3 pinches for this amount of onions - maybe around a teaspoon?

The salt causes the onions to release moisture, which means that liquid will evaporate in the pan leaving you with open access to the sugars in the onions. Yay caramelization! Plus, salty caramelized onions are delicious since they get so sweet on their own. :D

Step 5: Cooking the Onions, the First Half

There are two major things to remember when cooking caramelized onions:

  1. Stir and scrape the bottom often - every few minutes.
  2. Don't crank the heat over medium, as that is how you'll end up burning the onions instead of caramelizing.

For the first 20-30 minutes, the onions should continue to release quite a bit of liquid - keep the heat around medium and stir often - every few minutes. Scrape the pan clean every time - if you leave the stuck on sugars in place, they'll burn.

Near the end of this time, the onions will begin to dry out a bit and you'll need to keep a close eye on them. They'll also start to get a little golden brown. :D

Step 6: Cooking the Onions, the Second Half

After 30 minutes, you should definitely see color beginning to form on the onions.

I like to turn the heat down a little at this point and keep a closer eye on them. You'll probably need to stir and scrape them more often as well.

If you go to stir and they're sticking pretty bad, you can add a tiny splash of water. You'll need to either turn the heat down or stir more often to remedy this - you'll figure it out as you go!

I like to stir and then gently push the onions down into a flat even layer, but it's not necessary.

In another 15-30 minutes, the onions should be beautiful and caramelized. Keep them going as long as you want - I like mine to be mostly deep golden brown with a few lighter onions. :)

If you're running into issues, head to the next step to find fixes for the two major things that can go wrong!

Step 7: What to Do If Things Go Terribly Wrong

(Pictured above - scraping off the scary accidental burnination)

Caramelized onions are not the easiest thing to cook because they do require constant babysitting and awareness about what's going on in the pan. But you can fix nearly everything that goes wrong unless you just burn them to a crisp. ;)

My onions have burned to the bottom of the pan - OH GOD WHAT NOW?

If you go to stir the onions and they're sticking badly and the bottom of the pan is a dark brown or black, you've got your heat too high or you're not stirring often enough. But you can fix it!

Turn the heat off (or very low) and push the onions to the sides of the pan. Scrape up the dark burned sugars in the middle with a wooden spoon. Throw this bit away! Then add a couple tablespoons of water, turn the heat back up and stir it around.

If you see any onions that have gone black, chuck those as well - anything black will make the caramelized onions bitter.

My onions are limp and colorless and it's been forever.

You probably don't have your heat high enough - if you're seeing a lot of steam and liquid in the pan, turn up theheat to medium or slightly above. Stir frequently for a few minutes until the steam and liquid dissipates. Then turn the heat back down and continue as normal.

I would not add any more salt at this point without tasting, though.

You may also need to add more fat or oil if the onions aren't getting any color after a few minutes.

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