How to caramelize onions slowly without burning them

Learn the honest timeline and low-heat method for deep, sweet caramelized onions, plus the splash-and-scrape trick that stops burning. It suits home cooks who keep ending up with bitter or half-raw onions. All you need is onions, oil or butter, salt and a heavy pan.

NEVER Caramelize Onions Like This Again — Try This Old Italian Trick, by Rosa Mancini on YouTube. 14 min 39 s.

Video length
14 min 39 s
Time to do it
1 hour 15 minutes
Difficulty
Easy
Steps
8

What you need

Steps

  1. Peel the onions and cut them root to tip, from the stem end down through the root. This keeps the slices together during a long cook instead of falling apart.

  2. Slice the onions into even pieces about 3 mm thick. Even slices cook at the same rate, so some do not burn while others stay raw.

  3. Warm a heavy pan over medium-low heat and add enough oil or butter to coat the bottom. Do not use high heat, which scorches the sugars and turns onions bitter.

  4. Add the onions and a good pinch of salt right at the start. The salt draws out water and helps them soften and brown evenly.

  5. Stir every few minutes and keep the heat low. Expect 45 to 60 minutes, not the 10 minutes many recipes claim.

  6. When the pan looks dry or the onions start to stick, splash in a little water and scrape up the brown bits with your spoon. Repeat as needed.

  7. For a faster result, cover the pan with a lid for the first 15 minutes to soften the onions, then uncover and cook slowly until deep brown.

  8. Cook until the onions are soft, sweet and a deep golden brown. Taste and add more salt only if needed.

Tips and common mistakes

Skip added sugar. Slow cooking releases the onions' own sweetness, and sugar burns easily.

If you use baking soda to speed browning, add only a tiny pinch, as too much turns the onions mushy and soapy.

Chill the onions for 10 minutes before cutting and cut near a running fan to cry less.

Cook a big batch and freeze portions flat in bags so you always have some ready.

Questions

How long do caramelized onions really take?

On low to medium-low heat, plan on 45 to 60 minutes. Faster methods work but give less sweetness and depth.

Why did my onions turn bitter?

Usually the heat was too high, so the sugars scorched before the onions softened. Lower the heat and splash water when the pan dries.

Can I caramelize onions in the oven?

Yes. Toss sliced onions with oil and salt on a tray and bake at about 200 C, stirring every 15 minutes, for 45 to 60 minutes until deep brown.

This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.

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