There Are No Shortcuts When It Comes to Caramelized Onions
People love a good cooking hack these days. Any method, ingredient, or piece of equipment that can save a little time or effort is like a godsend since most of us have little time or effort to spare.
My professional cooking background was in fine dining, the province of classically trained chefs who thought shortcuts were cheaters’ crutches that yielded inferior results. So we often did things the hard way, for better or worse. But I came to learn that sometimes the hard way was, in fact, the best way.
Caramelizing onions is exactly the kind of slow, tedious process that cooks want desperately to hack. It takes the better part of an hour and requires strategic stirring and heat manipulation. But after testing both a “quickie” stovetop caramelization approach and also a slow-cooker method, I still feel the classic technique is best by far. The good news is that, done right, it’s actually easier and less tedious than you might think, as you’ll see.
First, a look at where the hacks go wrong.
The “Quickie” Method
Some years ago, a young cook in our test kitchens told our staff that one of her cooking school instructors endorsed a high-heat, quick-caramelizing method for onions. They’d cook to perfection in less than 15 minutes, she said, and be just as good or better than traditionally caramelized onions.
The idea was to keep the pan over medium-high heat the whole time, sautéing (stirring frequently) until the onions reached the desired brown color. We were skeptical. So we tested the techniques side by side.
The results were obvious before we even tasted them. Just looking at the finished pile of high-heat onions, we saw how unevenly cooked they were. Some pieces were light blond. Others were deep brown. Some unfortunate onion slices were both blond and blackened at the edges.
The texture was just as uneven, with al dente bits mixed in among the more tender onion strands. The conclusion was clear: to brown the onion’s natural sugars evenly, you need to cook them for a long time over low heat.
The Slow Cooker Method
Some cooks find this method fuss-free and practically foolproof. In my own test, I ran into problems that made me doubt the supposed convenience.
Even cooked on the low setting, the onions need occasional stirring to caramelize uniformly. Without stirring, you end up with the same uneven results as in the quickie test.
What’s more, the onion’s liquid content never cooks off properly, so you get what looks like French onion soup. Some cooks just discard the extra liquid (sacrificing the flavor in that liquid), while others advise cooking the browned onions uncovered at the high setting for an hour or so to reduce the juices.
If you could just put your oil and sliced onions in a slow cooker and open the lid 10 hours later to discover caramelized perfection, I’d be all in. But you can’t. My feeling is that if I need to be stirring the pot, covering and uncovering, and manipulating the heat (for hours at a time, no less), I’d rather do it the old-fashioned way.
The Traditional Method
Here are a few tips to help you nail the traditional stovetop method:
Slice the onions vertically (i.e., pole-to-pole). Because of the onion’s fiber structure, vertical slices will hold their shape better when cooked to complete tenderness.
Use a shallow pan. This will let steam can escape easily.
Butter is great for browning and flavor, but olive oil works just fine. Make sure to use enough fat—say two tablespoons per three pounds of sliced onion. You can always drain off any excess when you’re done.
Start by cooking the onions over medium-high, stirring frequently, until they’ve started to soften and wilt down in the pan.
Turn the heat to medium-low, and cook them uncovered, stirring occasionally so they brown evenly.
If they stick a little here and there and form brown spots on pan, don’t worry: this is normal and actually good. Add a couple tablespoons of liquid to the pan (water or chicken stock), and scrape the brown spots to deglaze. The liquid lets the flavor and color of that delicious dark brown fond spread evenly throughout the mixture.
Yes, it takes longer than the high-heat approach, and requires a little more stirring than the slow-cooker method. But it delivers uniformly browned, wonderfully sweet and succulent caramelized onions every time.