Sumac onions are a tangy and slightly sweet condiment made by marinating thinly sliced red onions in a mixture of sumac and lemon juice.
It’s a staple in Middle Eastern and Mediterranean cuisine, adding acidity and flavour to rich dishes like grilled meat, seafood and falafel. Or use it to top salads, sandwiches and burgers.
It’s a flavourful side dish and condiment all in one.
Does a raw onion salad sound too intense for you? Don’t worry. Soaking the onions in cold water reduces the pungency of the raw onions. And instead, a slightly sweet, somewhat tart onion side dish rewards your patience.
Best of all? This easy sumac onions recipe requires only three ingredients.
What are sumac onions?
Sumac onions are a Middle Eastern condiment made by marinating thin slices of red onion in a mixture of sumac and lemon juice. Other optional ingredients include olive oil, fresh parsley and red pepper flakes.
The main component of sumac onions is raw red onion. But, it is the sumac marinade that gives the dish its fresh and zesty taste.
You can call it Turkish onion salad, sumac onion salad, red onion salad, raw onion salad, sumac marinated onions, or sumac salad. But it’s the same deliciously tart marinated onions that pair perfectly with Mediterranean and Middle Eastern food.
What is sumac?
Sumac is a spice derived from the dried and ground berries of the sumac bush. Its tart lemony flavour makes it a versatile ingredient for sweet and savoury dishes.
It is a staple in Middle Eastern and Mediterranean cuisine and adds a distinct tart and slightly sweet taste to dishes.
Use sumac powder in rubs, marinades, and salad dressings. Add sumac at the end of cooking for soups and stews to maintain the bright colour and flavour. Or sprinkle it on top of finished dishes as a seasoning.
Why this recipe works
If you’re unfamiliar with sumac marinated onions, you may do a double take at the thought of a raw onion salad. But this traditional Middle Eastern condiment has a tart and slightly sweet flavour without the pungent raw onion taste.
- Soaking thinly sliced red onion in cold water reduces the spicy compounds. It allows the natural sweetness of the onions to shine. And it’s a great trick to sweeten raw onions for green salads while keeping the onions crispy.
- The acidity of the sumac and lemon juice macerates the onion into a softened tart onion salad, not unlike quick pickled onions.
Sumac onion salad ingredients & substitutions
This easy red onion salad requires only three ingredients and a pinch of salt:
- Red onion: I use red onions for the colour and sweet flavour, but it’s delicious with banana shallots (as Yotam Ottolenghi uses in his sumac marinated onions from Simple). You can also use white onions or yellow onions if that is what you have – add a few drops of pomegranate molasses to sweeten the salad if needed.
- Sumac: The deliciously tart sumac spice gives this condiment its flavour and distinctive speckled look. The best substitute for sumac powder is ground black limes.
- Lemon juice: Freshly squeezed lemon juice turns the sumac spice into a marinade. You can also use apple cider vinegar or red wine vinegar if you don’t have any lemons around.
Optional sumac onion add-ins
You won’t stray far from traditional Turkish onions by including a few optional extra ingredients:
- Red pepper flakes: Add a spicy kick to your marinated onions. I love to add half a teaspoon of Aleppo pepper (Turkish pul biber), but any chilli flakes will do.
- Parsley: Finely chopped parsley pushes this condiment closer to the salad category. It adds fresh flavours and a vibrant green contrast. Use flat-leaf parsley or the curly variety.
- Pomegranate molasses: This thick, syrupy reduction made from pomegranate juice, sugar, and lemon juice is another beautifully tart addition to the raw onion salad.
- Olive oil: A tablespoon of extra-virgin olive oil will give the sumac onion salad a luscious texture.
With only these simple ingredients, sumac onions are gluten-free, plant-based, and super delicious. Perfect for easy entertaining.
How to make sumac onions
Sumac onions are a perfect Middle Eastern condiment. And, bonus, they’re also super easy to make.
There are two steps to make sumac onions sweet and tart without that pungent onion flavour.
- Finely slice onions and leave them to soak in cold water for at least 10 minutes (up to 30 minutes).
- Thoroughly drain the onions, then mix them with sumac, salt and a bit of fresh lemon juice.
Both steps will reduce the pungency of the onions and reward you with a slightly sweet and tangy onion salad. Find the instructions in the recipe card.
How to store red onion salad
Transfer your sumac onions to an airtight container and refrigerate for up to five days.
It’s best to store them in a non-reactive container, such as a glass jar or plastic container, to prevent the flavours from being affected by metal.
The onions will continue to soften and turn bright pink throughout. If they become too tart, you can rinse them with cold water and add a pinch of sugar for sweetness.
Drain the liquid before serving if the stored onion salad becomes too watery.
Sumac onion serving suggestions
Sumac onions are a traditional side dish that adds fresh acidity to rich meals like grilled meat.
But that’s not all. This marinated red onion salad is are a versatile condiment that will bring freshness and a touch of colour to any meal.
Use it as a zesty salad topping
Add the sumac onions to tomato salad like Ottolenghi does in his recipe for tomatoes with sumac onions and pine nuts from Simple. Or use it instead of the black lime onions in this tomato pomegranate salad.
You can also add it to Middle Eastern salads like fattoush or bulgur wheat salad.
Serve sumac onion salad as part of a mezze spread
Sumac onions make the perfect accompaniment to a variety of Middle Eastern dishes.
Make a falafel plate with crispy Middle Eastern falafel (or try this simple baked falafel), creamy lemon hummus, lemon tahini sauce, fresh vegetables (like tomato wedges, cucumber slices and red bell pepper) and a bowl of sumac onions. Find more ideas for your falafel plate and what to serve with falafel.
Or serve the sumac onions with a mezze spread. Try a Middle Eastern bulgur wheat salad with dips like harissa hummus, muhammara (Lebanese red pepper and walnut dip), marinated feta, or garlic and herb labneh balls.
Serve it with lots of warm pita bread, fresh veggies and extra-virgin olive oil.
Add it to sandwiches, wraps and burgers
Sumac onions are the perfect condiment for Middle Eastern sandwiches like chicken shawarma, kebab, gyros or falafel pita sandwiches instead of raw onion.
Or use it to top your next burger instead of onion relish.
Use it in dips and spreads
Mix sumac onions with yoghurt or sour cream to create a delicious dip for veggies or pita chips.
Or spread a shallow plate with labneh, spoon over some sumac onions and top with chopped pistachio or toasted pine nuts.
Top a grain bowl with sumac onions
Prepare a bowl of quinoa kale salad or bulgur wheat salad as the base of your grain bowl (or use brown rice, barley or your favourite cooked grain). And top it with avocado, veggies, nuts and a tahini dressing for an easy flavourful meal.
Frequently asked questions
Sumac onions are a Middle Eastern condiment of thinly sliced onions marinated in sumac spice and lemon juice. The result is a tangy and slightly sweet flavour that pairs well with Middle Eastern food.
Serve sumac onions (red onion salad, raw onion salad, or sumac marinated onions) with grilled meats, salads, gyros or crispy falafel.
Sumac has a tangy, slightly sour flavour with a hint of sweetness reminiscent of fresh lemon juice and berries. Its mellow lemon taste is not overpowering, making it a versatile ingredient in many dishes.
Sumac is commonly used in Middle Eastern and Mediterranean cuisine to add acidity to meat dishes, salads, dips, and more.
You can reduce the spicy compounds by soaking sliced onions in cold water. It makes the onions sweeter and keeps them crispy. Allowing the sliced onions to soak in vinegar or lemon juice will remove more of the pungent flavour, but the onions will soften and absorb the sour taste.
Cooking the onions over low heat will also allow them to soften and become sweeter.
- Mandolin (optional)
- 1 red onion
- 1 tablespoon sumac
- 1 tablespoon lemon juice
- ⅛ teaspoon salt
- Cut the red onion in half. Then slice it into thin half-moons – I like to use a mandolin for even slices, but you can use a sharp knife. Place the red onion slices in a bowl of cold water and leave for at least 10 minutes (up to 30 minutes).
- Thoroughly drain the sliced onions and mix them with the rest of the ingredients. Use your hands to massage the sumac into the onions.
- Set the red onion salad aside for the sumac marinade to do its magic. Leave it for at least 20 minutes before serving.
- Transfer leftover sumac onions to a non-reactive airtight container and refrigerate for up to 5 days.