French-Fried Onions

If you french-fry onions, add a whole onion to however much you think you'll need. Maybe two if you have kitchen help. (And please don't forget the dishwashers. We work hard.) These things are ridiculously hard to avoid snacking on while you're cooking, and you'll want enough left over for your dish. Onions are cheap. Enjoy your privileged position in the kitchen.

French frying onions is pretty easy*:

  1. Halve, quarter, or keep the onions in rings, then slice them very thin. The thinner the slice, the crispier the result, but if they're too thin, they'll be very fragile. For the sake of argument, figure 1/8 inch. (For fast food style onion rings here, you'd slice thick and maybe blanch as you would green beans.) If you've been looking for an excuse to buy a mandoline, here it is.
  2. For each batch: Toss in flour until the pieces naturally separate and everything is covered. You can season the flour first if you like: Salt and pepper, maybe a little paprika, annatto, and/or turmeric for a color boost or flavor twist. If I were making them only for myself, I'd add a hearty dose of cayenne.
  3. Do see the (*) note below about this step. Shake off excess flour and fry in hot oil until crispy and as deeply colored as you want them to be. Be careful not to cook too many at one time: The more they touch in the cooking oil, the less crispy and the greasier they'll be.
  4. Remove with a flat strainer to paper towels or a rack. Don't leave them there long enough to cool completely, or the salt in the next step won't stick. If you don't have a flat strainer, you can get by with a slotted spoon. Work quickly and be extra careful not to slosh too much oil along the way.
  5. Toss (gently!) in a big bowl with salt or the stuff you used in step 2 above.
  6. Taste and adjust seasonings. It's not too late to cut that extra onion.
  7. Transfer (gently!) to wherever you're accumulating them. A large wire rack is ideal, but you can use whatever you want. The goal is to give them as much room to spread out as you can. The deeper the pile gets, the more they'll break and get greasy. A plate covered in crumpled paper towels will work in a pinch.
  8. Repeat from step 2 above.
  9. (Optional.) If your final serving dish can handle it, you can toss the assembled dish under a broiler for a final crisping before taking it to the table.

* I say frying onions is "pretty easy", and in a commercial kitchen it is ridiculously so. With a proper mise en place and commercial grade equipment, you can go from a dozen whole onions to a giant pile of crispy goodness in a matter of minutes. But the home cook doesn't have a big ol' deep fat fryer at the ready, and it's a lot more hot oil than we usually use.

The oil has to be deep enough to completely submerge the onions while they cook. That is a lot of oil, which can be expensive. And you can't just dump it down the drain, so it's in the way while you wait for it to cool enough to clean up. And then you have to store or dispose of the oil. Nothing insurmountable.

You'll get the best results from a wide flat pot filled about a third full. Don't go more than half, though, because of expansion: All that golden, glorious bubbling that only a deep fat fry can bring. You don't want to go much less than a third full or the oil will cool off too much when you add the onions. Cooler oil will take longer, which results in a less crispy, more greasy result.

As for cooking temperature, figure somewhere between 350°F and 375°F. You want to stay comfortably under your oil's smoke point, and your temperature recovery is only as good as your stovetop. If you don't have a frying thermometer, drop just a single small piece of dusted onion in. If it fries happily right away, you're there. If it's languid, turn it up or let it heat for a little longer. If it seems a little manic, you're running hot: Get those onions in immediately or remove the pot from the heat. If the oil looks weird or shadowy, you're close to its smoke point, so get it off the heat for a little while and turn down your burner.

For oil to use, plain ol' vegetable oil (whatever that happens to be) is probably your best choice. Expense aside, you don't want to use something flavorful--EVOO or almond oil, for example--because those flavors burn easily and unpleasantly. Peanut oil is nice, but probably not worth extra effort or expense. I expect Canola oil is fine. Maybe corn.

A version of this essay first appeared as a Reddit comment.