How long does it really take to caramelize onions? It depends on whether you want lightly browned, softly cooked onions, in which case you can probably get away with 20 minutes or so. But really deeply browned and truly caramelized onions (as opposed to simply burnt and crispy) can take up to an hour over low heat.
Are there shortcuts? Scocca reviews a method from Melissa Clark (one we've also reviewed) and concludes grumpily that, "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."
I went back and ruffled rather nervously through The Kitchn's archives; were we also guilty of underquoting this caramelized onion time? I think we may skirt the truth a bit; we often say it takes 20 minutes, although this won't always get you all the way there.
But why do recipe writers so often drastically undersell the real time it takes? Scocca thinks that it is because there is a stopwatch on many recipes; writers are being pushed to create quicker and faster recipes, and caramelized onions don't fit neatly into a 30-minute fast dinner. And yet, even though caramelized onions do take a long time to cook, they make up for the time in convenience; Scocca recommends making a big batch while you're in the kitchen doing something else, or throwing a load of onions into the slow cooker. Not fast, but convenient, yes. Also? Worth their weight in gold, for flavor. Just don't lie about how long they take.
Read the article: Layers of Deceit: Why do recipe writers lie and lie and lie about how long it takes to caramelize onions? at Slate
(Image: Anjali Prasertong)