The #1 Ingredient for Better-Tasting Caramelized Onions, According to Samin Nosrat
A hint can be found in the title of her book and Netflix series "Salt, Fat, Acid, Heat."
As we anxiously await the next incarnation of chef/author/TV host Samin Nosrat's Netflix series Salt, Fat, Acid, Heat (psst...here are 29 essential cooking lessons learned during season one from our pals at Food & Wine), she's been keeping busy with a timely, pandemic-friendly podcast.
In the latest episode of the podcast Home Cooking, which Nosrat co-hosts alongside her pal Hrishikesh Hirway, she tackled a variety of queries from challenged home cooks with issues related to bay leaves, non-fruit baking, a daunting cucumber surplus and more.
Hirway and Nosrat shared savvy advice (plus plenty of laughs and epic food puns) during the hour-long episode, but our favorite technique tip came about 45 minutes in, when listener Hannah called in with an allium inquiry.
"I was wondering how you caramelize an onion. I can sauté onions, I can cook them, I can get some flavor into them, but I can not properly caramelize an onion for the life of me and I was wondering if you could offer some support," she said.
First things first, don't waste your time by caramelizing an onion, Nosrat advises. Caramelize onions. Do at least four at a time, Nosrat says, since they will keep well in the fridge for several days to use on pizzas, toast, burgers and more. Yellow onions are Nosrat's favorite variety for caramelizing, but red, spring, Walla Walla and white onions all work well, too.
Related: 30 of Our Favorite Onion Recipes
Slice those onions, get a pan (preferably a cast-iron one like this Lodge Pre-Seasoned Cast Iron Skillet; $22.97, Amazon) warm—not scorching hot—then melt a mix of butter and olive oil in the pan. A bit of both works well for ample browning and the best flavor, Nosrat says. Add the onions, season with salt early in the process to draw out some of the water, then allow the onions to gently brown for about 20 to 30 minutes ("taking them as dark as you like," Nosrat says), stirring every few minutes.
"This is where the magic comes in," Nosrat says. "To finish a caramelized onion, because you've built all of that sweetness and flavor and richness, you want to balance it with acid. Sometimes people will add a bit of balsamic vinegar. What I like to do is add a 'secret' amount of red wine vinegar." (Try something like this Greek Red Wine Vinegar; $9.99, Amazon.)
So what does a "secret" amount actually translate to? About 1 teaspoon per 4 onions—so little that you don't actually taste the vinegar itself, but it balances out the sweetness of the onions. Add a few drops, give it a stir, taste test and add more vinegar and salt as needed.
Voila: Picture-perfect, golden-brown, beautifully balanced caramelized onions ready to enjoy now or freeze in muffin tin portions for quick and easy flavor-boosters any night of the week.