How Long Do Onions Take To Cook

Food

Layers of Deceit

Why do recipe writers lie and lie and lie about how long it takes to caramelize onions?

480911650 — How long does it *really* take to caramelize onions?
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Browning onions is a matter of patience. My own patience ran out earlier this year while leafing through the New York Times food section. There, in the newspaper of record, was a recipe for savory scones with onions, currants, and caraway. Though I wasn't particularly interested in making savory scones, one passage caught my eye:

Add the onions to the skillet and increase the heat to medium-high. Cook until they begin to turn dark brown and somewhat soft, about 5 minutes. Add the oil and a pinch of the fine sea salt; continue cooking until the onions are soft and caramelized, about 5 minutes longer.

Soft, dark brown onions in five minutes. That is a lie. Fully caramelized onions in five minutes more. Also a lie.

There is no other word for it. Onions do not caramelize in five or 10 minutes. They never have, they never will—yet recipe writers have never stopped pretending that they will. I went on Twitter and said so, rudely, using CAPS LOCK. A chorus of frustrated cooks responded in kind ("That's on some bullshit. You want caramelized onions? Stir for 45 minutes").

As long as I've been cooking, I've been reading various versions of this lie, over and over. Here's Madhur Jaffrey, from her otherwise reliable Indian Cooking, explaining how to do the onions for rogan josh: "Stir and fry for about 5 minutes or until the onions turn a medium-brown colour." The Boston Globe, on preparing pearl onions for coq au vin: "Add the onions and cook, stirring often, for 5 minutes or until golden." The Washington Post, on potato-green bean soup: "Add the onion and cook for 8 to 10 minutes, stirring occasionally, until golden brown."

If you added all those cooking times together end to end, you still wouldn't have caramelized onions. Here, telling the truth about how to prepare onions for French onion soup, is Julia Child: "[C]ook slowly until tender and translucent, about 10 minutes. Blend in the salt and sugar, raise heat to moderately high, and let the onions brown, stirring frequently until they are a dark walnut color, 25 to 30 minutes." Ten minutes plus 25 to 30 minutes equals 35 to 40 minutes. That is how long it takes to caramelize onions.

Telling the truth about caramelized onions would turn a lot of dinner-in-half-an-hour recipes into dinner-in-a-little-over-an-hour recipes. I emailed Sam Sifton, the Times food critic turned national editor, to ask if the Recipe Writing Guild had some secret agreement to print false estimates of onion-cooking time. He wrote back: "I can reveal that onion caramelization takes longer than the Guild believes. But it need not take as long as you believe it to take! You can speed it up with butter, so long as you are careful not to burn."

Could onions be browned, at all, in 10 minutes? I embarked on a quest to find out. Someone on Twitter had suggested things would go faster with sweet onions. This seemed a little like pepping up a bread pudding recipe by treating sliced pound cake as a kind of bread. But I bought a Tampico sweet onion, chopped half of it into tiny bits—only half, so as not to crowd the pan—and turned my biggest burner as high as it would go. Butter seemed a little risky at that temperature, so I went with olive oil, in a cheap, lightweight nonstick skillet. In five minutes, a few flecks of brown had appeared among the otherwise raw-looking onion bits. After eight minutes, some of the onion had begun to take on the scorched aspect of the unfortunate onions stuck to bagels. At the 10-minute mark, the brown flecks had turned black, in a mince that was a mix of brown and still-pale bits. The onion was done cooking—that is, it was beginning to be ruined—but it was not very well caramelized. At 11 minutes, I scraped an inedible mess out of the pan.

But the onion lies had not yet been fully refuted. Melissa Clark, the author of the Times' scone recipe, claimed in a Diner's Journal post that she relies on "a somewhat unusual technique," one that "takes less than half the time of the traditional slow-cooked method of caramelization and makes for sweeter, more intensely flavored onions with a complex, chewy texture." The secret, she writes, is starting the onions in a dry pan, and adding the oil later.

Note that half the time of the traditional method is still 20 minutes, not 10. Nevertheless, I decided to follow her instructions to the letter. I used a red onion, as Clark specified, "halved through the root and thinly sliced crosswise." I started slicing it paper-thin. Not good enough? I got out the knife sharpener and touched up the edge on the cleaver. Now it was tissue-paper thin. I heated the pan—dry—over a generously medium-high flame, then added the onions.

After five minutes—when according to Clark, it would "begin to turn dark brown and somewhat soft"—the onion was resolutely white and pink, and only slightly translucent. I added the oil: one tablespoon, extra-virgin. The white parts turned the color of extra-virgin olive oil.

At 10 minutes, when it was supposed to be done, the onion was translucent and soft, with only a tinge of gold. Soon after, one golden speck appeared. By 15 minutes, the onion was even softer and more golden. At 20 minutes, there were deep brown patches, and I was afraid they would scorch while I set down my spatula to take notes. At 24 minutes, the risk of scorching forced me to lower the heat to medium. By 25 minutes, they were pretty well caramelized, and at 28 minutes they were as done as I'd want.

So Clark was only off by 180 percent on the cooking time. You can save 12 minutes off caramelizing onions, provided you pin yourself to the stove.

That is the deeper problem with all the deceit around the question of caramelized onions. The premise is wrong. The faster you try to do it, the more you waste your time. This isn't some kitchen koan. It's a practical fact. The 10-minute-cum-28-minute caramelized onion is all labor and anxiety. Give yourself 45 or 50 minutes to brown onions, working slowly on a moderate flame, and it's an untaxing background activity. You can chop other vegetables, wash some pots, duck out to have a look at the ballgame on TV in the next room. Keep half an eye on the pan. It will only need close tending toward the end.

Recipe writers approach kitchen time with a stopwatch. The Times' scone recipe, as written, claimed to take 45 minutes. Once you subtract out the (fictitiously shortened) onion-cooking time, the one-minute caraway-seed-toasting time, the 15-to-17 minute baking time, and the 10-minute cooling time, that leaves the cook seven to nine minutes in the middle to mix the dough (including grating frozen butter into it), shape it, cut it into scones, and lay the scones out on a parchment-lined baking sheet. Oh, and somewhere in there, the onions needed to "cool completely." Isn't home baking soothing?

In truth, the best time to caramelize onions is yesterday. Often enough, you need to have them ready before you can start on the rest of the dish. Thus the recipe-writers' impulse to deceive. Browning onions is slow work, and it comes first. So get a pan going after dinner, and they'll be ready when you need them. Or throw the onions in a crock pot and go to bed. In recipe time, that's hours and hours. In your time, the time that matters, it's less than five minutes.