Melted Onions Recipe on Food52 (2024)

FAQs

How do you melt onions? ›

Place sliced onions in a 9x13-inch casserole dish. Add olive oil, salt and pepper, and toss to combine. Cover the pan with foil and bake for 1 hour. Remove the pan from the oven, lift the foil, and stir the onions.

While you can start the cooking process at medium heat, low and slow is the name of the game when it comes to caramelizing onions. Once your onions begin to soften and take on a golden hue, you'll want to reduce the heat from medium to medium-low or even low for the remainder of the cooking process.

Onions release amino acids that react with sugar as they heat up. It's this chemical reaction that creates wonderful flavors and changes in color. And if you've tasted caramelized onions before, you've experienced this magic first hand. They aren't just sweet.

Okay, it's counter intuitive, but you need to add water. Cook on high with the pan covered. The additional water generates steam, that in turn transfers much more heat to the onions than otherwise.

Caramelize the onions: Heat about 1 tablespoon of canola oil in a large skillet or dutch oven over medium-low heat. Once hot, add the onions and stir to coat. Let cook, stirring every 5-10 minutes, until deeply caramelized, about 1 ½ - 2 hours.

Our Test Kitchen likes to use butter when caramelizing onions, as it offers the richest flavor. If you avoid dairy or don't have butter, you can caramelize onions in other fat such as margarine or olive oil. Add the onion slices. It's okay if they overlap a bit here because they'll shrink as they cook down.

Cover the pot with a lid, and then turn the burner on to medium-low heat. Cook covered until the onions have mostly broken down and are a pale brown sludge (about 45-60 minutes). Be sure to stir the pot periodically, checking to make sure the onions aren't burning.

If you need to caramelize onions quickly, adding sugar or a pinch of baking soda (to raise the pH level and help them brown quicker) can help to speed up the caramelization process but truly they aren't a dish that cooks up quickly. If using baking soda I'd suggest about 1/4 tsp per pound of raw onions.

What is the difference between caramelized onions and cooked onions? ›

As for how these onions compare to sauteed onions the big difference is time. Sauteed onions don't spend as much time on the heat. They get soft and they may brown a bit, but sauteed onions only take a few minutes and still retain their sharp, onion flavor. Caramelized onions are a labor of love and taste sweeter.

You're not sautéing your onions—you're trying to slowly coax flavor out of them. It takes time, probably a solid 45 minutes, for the onions' sugars to caramelize. If your heat is too high, the onions will burn. Heat your pan over medium-low, then add your onions.

Tip: use apple cider vinegar for white and yellow onions and balsamic vinegar for red onions. Tip: the vinegar serves to deglaze the pan, adds acidity, and brings this recipe together by boosting the tangy and savory flavors of the caramelized onions. If the onions stick to the pan, that's fine.

The trick is to use a heavier pot or pan—a tri-ply stainless steel saucepan or enameled cast iron Dutch oven is ideal—that can transfer heat slowly and evenly, preventing the hot and cool spots that are the bane of good caramelization.

Baking soda makes the onions more alkaline, which speeds up the browning reactions necessary for properly caramelized onions. But it also weakens the pectin that holds the onion's cells together, turning what should be soft but distinct pieces of browned onion into a nauseating stew of pea-green mush.

No-sweat sweated onions

Instead of spending 15 minutes trying to soften onions in a pan (only to scorch them!), try this microwave method. Pop chopped or sliced onions in a bowl, add a spoonful of water, cover with a plate and microwave on high for 3-4min. Carefully remove (the bowl will be very hot) and uncover.

Sauteing onions: Softens them, most people prefer not to run into raw onions in their sauce. Onions will cook in a sauce, but very slowly, so frying them before makes sure they will be soft even if your sauce has a fast cooking time. Releases sugars, making them taste sweeter.