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About a year ago, I wrote a post on how to make French Onion Dip, in which I talked about ways to speed up the traditionally hours-long process of caramelizing onions. The end result? There are a couple of tricks: add a touch of sugar at the beginning (to give caramelization a jump start), add a pinch of baking soda (caramelization and browning reactions take place faster at higher pH ranges), and blast it over high heat, deglazing with a bit of water every time it threatens to burn.
This week, I decided to challenge myself to see how fast I could caramelize onions without the "cheaty" additions of sugar and baking soda, relying only on heat and a bit of water to prevent burning. I managed to do it in 15 minutes and 22 seconds. Not bad, considering it can take over an hour to do the traditional way.
I'll just shut up and let the video do most of the talking.
As you can see, the key is good stirring and temperature regulation. I use a heavy Le Creuset enameled cast iron pot, which is great at transferring heat slowly and evenly, preventing the hot and cool spots that are the bane to good caramelization (a tri-ply stainless steel saucepan would also work well). Every time the fond (that's the browned bits of sugars and proteins that stick to the bottom of the pot) threatens to burn, I add a few tablespoons of water and use a wooden spoon to scrape the bits up. The browned sugars and proteins end up dissolving in the water then spread themselves evenly around the onions.
In no time at all, you have deep, dark, sweet onions.
The catch? Well, there is a catch, and for some it may be a deal-breaker: These caramelized onions are not as good as real-deal slow caramelized onions.
After using the method dozens of times and comparing it against traditionally caramelized onions, I've come to the sad realization that there are no real shortcuts here. That's the bad news. The good news is that they're about 90% as good as traditionally caramelized onions, so unless you're planning on a recipe that absolutely requires perfectly caramelized onions—a French onion soup, say—then these'll do you just fine. Throw them on your burger, spread'em on your pizza, rub it on your roast, mix it in with your coffee, or spread it on your toast.
Any technique is always a trade-off in one way or another, and I'm willing to sacrifice 10% of my flavor to save 80% of my work at least 94% of the time. You do the math.
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About the author: J. Kenji Lopez-Alt is the Chief Creative Officer of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.