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Cooking Tips

How to Caramelize Onions Fast

Caramelized onions can take more than an hour of careful cooking over a low flame. Our technique cuts that time in half.
By Published June 7, 2021

Caramelized onions improve everything from pastas and potato casserole to chip dips and, of course, French onion soup. But their sweet, complex flavor can come with a cost—sometimes more than an hour of careful cooking over a low flame.

In this video, part of our "Kitchen Smarts" series on our YouTube channel, Cook’s Illustrated test cook Lan Lam shares our technique for preparing caramelized onions in less than half of that time. To do this, we reviewed the science and questioned each step of the traditional approach. Here are some of our findings:

  • Cut the onions pole to pole instead of crosswise: Slicing the onions through their root end prevents them from breaking down too much during cooking.

  • Start cooking the onions with water over high heat and covered: Surrounding the onions with steam (and submerging some of them in the added water) heats them more quickly and thoroughly than just relying on the heat generated by the cooking surface of the skillet alone.

  • Press and stir the onions until deeply browned: Since browning occurs only where the onions are in direct contact with the hot pan, gently press the softened onions into the bottom and sides of the skillet to allow for maximum contact. Let them sit for about 30 seconds and then stir them until they’re softened and deeply browned.

  • Finish with baking soda: This boosts the onions’ sweetness by encouraging the breakdown of flavorless inulin into sweet fructose.

Watch our step-by-step tutorial:

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