Sliced red onions, marinated in red wine vinegar, olive oil and oregano make a fantastic side dish for salads and grilled meats. They're tangy, with a bit of crunch and a lovely silky coating.
I love to serve them with salads, grilled meats, on kebabs or with a Greek mezze board.

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I do love to make pickled red onions, but these marinated onions are a level beyond.
The onions are pickled for just 15 minutes in salt and red wine vinegar. This gives the onions that lovely tangy kick.
Then after that initial 15 minutes, we add in plenty of olive oil and some oregano.
The result is a tangy, silky, smooth onion with a nice bit of crunch.
These are my luxury onions.
📋 What do we need?

- Red onion - of course! You can replace with red shallots too.
- Red wine vinegar - I like these to help keep that vibrant pink colour in the onions, but you can replace with apple cider vinegar or white wine vinegar if you prefer.
- Olive oil - I prefer to use regular olive oil, so it doesn't overpower the flavour of the red onion, but you can use extra virgin olive oil if you really want that tangy-grassiness of extra virgin.
- salt and oregano - to add extra flavour. The oregano makes the onions smell delicious too.
📺 Watch how to make it
Full recipe with detailed steps in the recipe card at the end of this post.
👩🍳PRO TIP These onions will last for longer if stored in the refrigerator, but the oil will solidify, so you'll need to take them out of the fridge an hour or so before serving.

🍽️ What to serve them with
- Serve with Air Fryer Greek Chicken, creamy feta dip and fluffy flatbreads
- As a topping for a Juicy Cheeseburger or Fish Tacos
- Alongside BBQ Lamb Souvlaki
- As a tangy addition to my Easy Pasta Salad
How would you serve them? I'd love to hear in the comments below.

🍲 More fantastic sides to add that extra hit of flavour
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Marinated Onions
Ingredients
- 1 red onion - peeled and thinly sliced
- ¼ teaspoon salt
- 2 tablespoons red wine vinegar
- 6 tablespoons olive oil
- 1 teaspoon dried oregano
INSTRUCTIONS
- Add the sliced onions to a small bowl. Sprinkle over the salt and pour over the red wine vinegar. Stir together and put to one side for 15 minutes, giving it a stir a couple of times.1 red onion, ¼ teaspoon salt, 2 tablespoons red wine vinegar
- Add the olive oil and dried oregano and stir together.6 tablespoons olive oil, 1 teaspoon dried oregano
- Serve immediately or transfer to a clean air tight container to serve later (see storage information in notes section below).
Video
✎ Notes
They can be stored at room temperature, away from direct sunlight for 2-3 days. The flavour will continue to develop over this time. Refrigerate? If keeping for longer than a couple of days, store in the refrigerator instead (in a sealed container). They should keep for about 2 weeks. The oil will solidify in the fridge, so you'll need to remove from the fridge about 60-90 minutes before serving, to allow the oil to turn back to liquid. Leftover oil Don't throw away the oil from the marinated onions! It makes a tasty salad dressing as it is.
If you want to add more flavour, add a pinch of salt and pepper and an extra splash of vinegar.
You could also add in extras such as honey, dijon mustard, chilli flakes if you like. Nutritional information is approx, per serving (this recipe makes 8 servings).
Nutrition
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Raymond Wyatt says
5***** tasty onion love it
Charalabos says
Can we use this recipe with flour and frying them and be eating them as extra on dishes?
Karen C says
I've hardly let this marinate and sampled it....so good already! Thank you for this recipe. I'll also save the oil for making a dressing for salad as mentioned in the article.
Eleanor says
Love the addition of oregano with the olive oil.
I used them with cajun chicken and quinoa salad bowl 😋 Thinking Greek lamb next.
Nicola says
Marinated onions can you use white onion, instead of red onion, and white wine vinegar instead of red, looks very tasty, will try this.