Mmm… caramelized onions. I mean anything with the word caramel in it automatically means it has to be good, right?
Caramelized onions are easy to make, (once you know a few simple hacks, and get past the crying stage, of course).
Caramelization just means the browning of sugars. In this case, it’s the natural sugars that are found in onions. When you add heat, these natural sugars are released.
How to Make Caramelized Onions
You’ll want to start with more onions than you think you’ll need. Onions contain a lot of water that’s released during the cooking process, which is why you must start with such a large quantity.
After cooking, they reduce by more than half the amount you start with.
The Secret Ingredient
There is one secret ingredient to making caramelized onions so flavorful though.
And it’s patience.
Onions must be cooked at a low temperature to achieve even browning. Cooking them at a higher heat means burnt onions, so make these when you’re not in a hurry. Trust me.. you will not enjoy eating burnt onions.
What Onions Work Best for Caramelizing?
All onions are not created equal, and this especially rings true when making caramelized onions.
You can use yellow, white, or red onions, but avoid using sweet onions. Yellow onions are always my go-to since they’re so versatile and readily available. Plus, they caramelize nicely.
Deglazing the Pan
Deglazing is a cooking technique that helps remove the browned bits that have stuck to the pan during the cooking process.
So, what are the browned bits in the pan of your caramelized onions? They’re simply just the natural sugars that have been released from the onions and stuck to the bottom of the pan. These browned bits are called fond.
There’s a lot of flavor in the fond and to release that flavor, it needs a liquid to help break it up.
Deglazing liquids that work well: water, broth, vinegar (sherry, balsamic, red wine, etc.), wine. It’s really up to you though – whatever tickles your fancy (well, tastebuds in this case).
How to Achieve the Best Results
Make sure you don’t slice the onions too thin. Cutting them too thin will result in a higher chance of burning.
Avoid high heat. You’ll end up with burnt onions instead of caramelized.
Deglaze your pan. This means you’ll be removing all the caramelized bits that have stuck to your pan (fond).
Don’t remove the onions from the pan too early. You’ll miss out on that rich, caramel flavor.
Practice patience. Good things take time, and this is definitely the case when making caramelized onions
Use the right pan. Stainless steel or cast iron pans work well. Avoid using a non-stick pan.
Pro Tips for Cutting Onions
- Trim off the top of the root end where you can see the stringy roots still attached, but don’t cut far enough down that you cut the entire root off.
- Now cut the other end of the onion so you’re left with a flat surface.
- With the flat side down, place your knife in the middle of the root and cut down until you have two halves. Do this for all your onions.
- This allows the root to stay intact, which will hold the onion together while you’re cutting your slices.
- Peel all your onion halves and discard.
- Cut the onions into half-moon shapes moving toward the root until just before. Discard the root.
- Continue until you’ve cut all the onions.
The Best Caramelized Onions
- 5-6 cups of sliced onions about 2 large onions
- 2 tablespoons oil olive oil or avocado oil work great
- ½ teaspoon salt
- 4½ tablespoons deglazing liquid divided
- Heat your pan over medium heat (no higher) and once hot, add the oil to coat the bottom of the pan.
- Next, add the onions to the pan and mix them around to coat them in the oil and then spread them out into a somewhat even layer, letting them cook untouched for about 6-8 minutes.
- Sprinkle in the salt and give the onions a little stir.
- As they continue to cook, the onions will start sticking to the pan a bit more (this is when the fond starts forming).
- When you notice they’re starting to stick, deglaze the pan with about 1.5 tablespoons of liquid and then scrape the bottom of the pan to help break up the fond and stir the onions around.
- Continue cooking the onions while stirring occasionally. Once you notice them starting to stick again, deglaze the pan with another 1.5 tablespoons of liquid.
- Continue with this method until you’ve deglazed the onions for a total of three times.
- After 30 minutes, turn the heat down to low and let them caramelize and deepen in color for another 10 minutes before removing them from the heat.
- Store in an airtight container in the fridge for several days.