Another pet peeve (which this doesn't solve): Recipes that include "marinate overnight" or some such in the middle (which can be easy to miss), instead of telling you up front that you have to start the day before.
My favorite is the ‘30 minute recipes’ that involve overnight marinating, carmelizing onions, etc.
(That is great gaslighting in that vid, lol)
Not sure what you meant about the gaslighting.
That being said.
Caramelized onions should be a dark (nearly black) and warm brown color, not a neutral clay-soil brown. (Picture brown-sugar boba pearls.) They should have no water content, and should be visibly syrupy in texture. They should smell buttery + nutty + toasty; and should be extremely sweet, in that complex caramel way, with no trace of the original onion flavor remaining.
The onions in the video are none of those things.
These properties are all corollaries of what caramelization is, when it comes to onions: you're not only breaking down starches inside the onion into sugars, but then also fragmenting some of the resulting sugars into volatiles (diacetyl, furfural, etc), while polymerizing more of the resulting sugars into various caramel compounds.
The onions in the video have merely finished the first step: sweating. The cells of the onion have broken down, releasing simple sugars and water; but despite a few minutes' pan frying after breakdown, they're still wet and gloopy (and have quite a bit more cooking to go before they stop being so), because onions contain rather a lot of water, and rather a lot of sugar, and simple sugars are hygroscopic, i.e. they really want to hold onto nearby water.
The goal of caramelization is the same in an onion as it is in candy-making: you need to heat the sugar up until it melts and begins to react with things around it, both building up (polymerizing) and breaking down (fragmenting.)
Sugar melts well above the boiling point of water. So you can't caramelize anything until all the water is gone.
And that's why caramelizing onions takes around 40 minutes. 10 minutes on high heat to sweat the onions (as in the video); 20 minutes on med-high to drive off all the water; and a final ~10 minutes with careful watch-and-adjust temp control to actually caramelize the sugars, without burning them.
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In theory, you might be able to make this process happen faster... but not with any random store-bought onion, the day you buy it. You'd need to 1. freeze, and then thaw, the onion (to break down its cells), and then 2. desiccate the onion (i.e. keep it in a bone-dry environment with convective air) to pre-purge the lysed water from it. The result would be a "ready-to-caramelize" onion that would let you skip the first two phases of cooking. (The result would also now be incredibly non-shelf-stable, becoming a pile of mush after a day or two.)
Some people throughout history (who perhaps originated the idea of being able to caramelize an onion in 10 minutes) may have done both of these steps purely by accident! In fact, insofar as onions are storage vegetables often kept in a root cellar for months before consumption, and insofar as some root cellars can both get to below freezing and be very dry inside, I could see most historical people cooking onions for winter recipes having gotten this "speed hack" for free without even trying.
But an onion you buy at the store will have gone through neither of those steps. Caramelizing an onion the day you buy it will take 40 minutes, full-stop.
In the comments from the original article, which you can find on the Internet Archive, he says that these these are not exactly the same as 45 minute onions and he would only use them a certain recipes.
And again, he's not the only one. There are lots of videos and articles about it.
And my point—I'll state it again—is that while these 10-minute onions might be useful, they are not "caramelized onions" in any sense, because no actual caramelization has occurred. And so saying that "this is a way to make 'caramelized onions' in 10 minutes" is false.
These are, certainly, a 10-minute substitute for caramelized onions; but they can no more be used as an argument that "you can make caramelized onions in 10 minutes, actually" (as the GGP poster says) than the existence of rice pilaf is an argument that you can make risotto in 10 minutes. They're different things!
> An earlier version of this recipe suggested using sugar and baking soda for even faster results.
https://www.seriouseats.com/quick-caramelized-onions-recipe
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> help things along with a little bit of sugar. In science speak, caramelization is the oxidation of sugars. Here, those sugars are the natural sugars in the onions, but the addition of a small amount of white sugar adds an extra caramelization boost.
But I might not read it super carefully when recipe planning at the start of the week, which can result in scheduling mistakes.