Caramelised onions are easy to make, but need a lot of time to cook. If you see someone telling you they’re caramelising onions and it takes 15 minutes, or half an hour, those are not caramelised onions! They are lightly cooked.
So yes, it’s very time consuming, but not very much active work. If you pop them on the stove and work on other things, just coming back to stir every once in a while, you won’t even notice the time. Slow and low cooking is always worthwhile.
Add these to any savoury dishes for a touch of sweetness and a more complex flavour. These leek and onion pasties are a good example, but you can make caramelised onion hummus (page 181 of my cookbook), or add to simple pasta dishes, or more complex meals like a savoury mushroom wreath.
This is a good staple recipe you’ll want to have in your back pocket.
Ingredients

Ingredient Notes and Substitutions
- Onions: red, yellow, and white onions can all be used interchangeably. Shallots are good too (but more expensive).
- Wine: if you don’t drink wine or have it in the house, balsamic vinegar is an ideal sub here. Replace the full amount of wine with one tablespoon of balsamic vinegar. Apple cider vinegar works too.
Step by Step

1. Prepare: heat the olive oil in a large frying pan over low heat. Halve and thinly slice the onions, then place them into the pan.
2. Cook down: cook, stirring occasionally, for about two hours. Pictured here is after about half an hour and they are not nearly ready.
3. Keep cooking: the onions will slowly become translucent, then turn a light golden colour. They should reduce by at least half.
4. Deglaze: once the onions have caramelised, add the salt and pepper. Stir to incorporate, then add the wine. Stir through, cook for another five minutes, then remove from the heat.
Recipe Notes
Adding the wine (or balsamic vinegar) at the end of the cooking time deglazes the pan. This lifts all the delicious savoury bits that may have stuck to the pan during cooking and makes the onions much easier to remove. Win win.
It’s important to cook the onions on a really low temperature, and they should not be browning. Patience is the most important element.
Some people add a bit of sugar or honey to the onions to speed up the process slightly, which you can do, but I never bother.
How to Store
Storage: refrigerate for up to a week in a sealed container.
Freezing: caramelised onions freeze very well. I often make extra and freeze portions in airtight containers for later use, and recommend this, as it’s such a time consuming process. Freeze for up to a month.

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Expert Tips
- Keep it low and slow: if you see any browning, reduce the heat. The onions should not brown or become crispy.
- Use vinegar: we don’t drink and only have wine in the house for cooking, so more often than not, these are made with balsamic vinegar. For pizza in particular I prefer to make balsamic onions.
- Fill the pan: don’t worry about crowding the pan when you first add the onions. They’ll cook down significantly, as you can see above – my pan was overfilled and heaped over the edges when the onions were first added.
More Staple Recipes
Pickled Red Onions
Vegetable Broth
Spelt Pasta
Oat Milk
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Caramelised Onions
Ingredients
- 1 tablespoon olive oil
- 4 medium onions about 600g or 1 1/4 lb.
- ½ teaspoon sea salt
- ½ teaspoon black pepper
- 60 ml dry red wine
Instructions
- Heat the olive oil in a large frying pan over low heat. Halve and thinly slice the onions, then place them into the pan.1 tablespoon olive oil, 4 medium onions
- Cook, stirring occasionally, for about two hours. During this time the onions will slowly become translucent, then turn a light golden colour. They should reduce by at least half. If you see any browning, reduce the heat.
- Once the onions have caramelised, add the salt and pepper. Stir to incorporate, then add the wine. Stir through, cook for another five minutes, then remove from the heat.1/2 teaspoon sea salt, 60 ml dry red wine, 1/2 teaspoon black pepper
- Use the onions as you’d like, or refrigerate for up to a week in an airtight container. Freeze up to one month.
Notes
* For American cup measurements, please click the pink link text above the ingredient list that says ‘American’.
Nutrition
Nutrition is provided as a courtesy and is an estimate. If this information is important to you, please have it verified independently.

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