How High Your Heat Should Be For Perfect Caramelized Onions

Caramelized onions are a culinary secret weapon. Flavorful and sweet, these soft, slow-cooked onions can turn even the simplest of dishes into something rich and complex. They up the ante of game day veggie dips, complement cheesy pierogies, and work wonderfully atop any kind of bread. Spoon some over a homemade pizza or lunchtime sandwich for a gourmet twist.

If you've never attempted to caramelize onions, now is the time. As hot dog and hamburger season kicks into high gear, perfecting this onion technique will make you barbecue royalty. For a fancy take on a cheeseburger, Food & Wine recommends cooking onions in butter for a total of 35 minutes before spooning the caramelized result over your meat. How's that for an upgraded picnic?

Yet while caramelization may seem and taste complex, achieving it is actually easy. So long as you follow one central guideline. When it comes to achieving the perfect caramelization, slow and steady wins the stove. 

Using heat that's too high is the ultimate mistake in onion caramelization, says The Kitchn. If you turn up the heat, you run the risk of burning your food. Low temperatures are therefore your best friend. Don't rush, and you — and, more importantly, your onions — should be alright. If you're still nervous about burning, cook your onions in clarified butter. According to Bon Appétit, butter's clarified cousin has a higher smoke point than the original, and is less likely to burn. 

You can alternatively opt for oil, either alongside butter or in lieu of it. The Spruce Eats recommends warming your choice of fat at a temperature of around 310 to 320 degrees Fahrenheit. Although you ultimately want your onions cooking on low, it's standard to start the process on medium or even medium-high heat before reducing the temperature (via Serious Eats). The outlet also suggests adding your onions to the pot at the same time as your fat — pre-heating your pan increases the chance of immediate browning.

Once you get your onions cooking, don't stray far from the stove. Caramelization requires consistent stirring — and equally unwavering patience. Reaching your desired caramelization can take anywhere from 30 minutes to an hour, says Simply Recipes. Meanwhile, Serious Eats recommends cooking onions for one to two hours.

Oh, and if you thought there was a shortcut, think again. To truly achieve caramelization and perfect your batch of gooey, sweet onions, you have to put in the time. If you're prone to impatience, consider another technique.