Have you ever tried sumac onions? Also known as Biwaz in Middle Eastern cuisine, it's simply marinated red onions tossed with chopped Italian parsley and a zesty sumac-based marinade that will delight onion-lovers everywhere! Serve marinated onions with kofta kebab, falafel, or mix into a Middle Eastern salad!
Sometimes referred to as Turkish onion salad, biwaz allows you to quick-pickle raw onions, then pile them high on a shawarma pizza. They're also excellent in adobada tacos and as a side dish to other Mediterranean recipes.
The best part is that you likely have all the ingredients on hand, except perhaps for sumac powder. Sumac has a tart, lemony flavour and also releases a beautiful red tint when added to a dressing or other liquids.
Sumac powder is a regular in many of my recipes. If you follow my blog, you might as well get some, you'll be needing it often!
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😍 Why You'll Love This Recipe
- Biwaz can be marinated ahead of time!
- If you love tangy flavors, marinated red onions will be your go-to quick and easy side dish!
- Marinated onions don't only go with Middle Eastern dishes; they are also perfect on smoked hamburgers, hot dogs, and blackened fish tacos!
🔖 Ingredients & Substitutions
- Sumac: The ingredient that makes this recipe shine is the tart sumac powder. Sumac gives the onions their amazing flavor.
- Onion: There are recipes out there that call for white or yellow onion, but I recommend using red onion because of its natural sweetness. It just begs to be pickled!
- Parsley: I prefer Italian parsley to curly parsley. You can increase the parsley if you want a more dominant parsley flavor.
- Acid: Although you can technically only use lemon juice to make pickled onions, I like to use a combination of vinegar and lemon juice.
*See recipe card for a complete list of ingredients!
🧅 How to Make Marinated Onions
Step 1: Peel and slice the red onion into thin slices. Add onion slices to a bowl, along with the chopped parsley.
Step 2: Whisk lemon juice, vinegar, olive oil, sumac, salt, and sugar in a small bowl.
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Step 3: Pour the sumac dressing over the onions and parsley, then whisk thoroughly to blend the ingredients.
Step 4: Allow the flavors to come together for an hour or so before serving with your favorite dishes!
🍽 How to Serve Marinated Red Onions
Serve marinated red onions with kubba Mosul, sumac chicken, in tri-tip sandwiches. Mix them into fattoush salad, add them to a gyro pita and a chicken shawarma plate, or use them as a topping for vegan biryani.
🤷🏻♀️ Recipe FAQs
Sumac imparts a tart, lemony flavor that's sometimes compared to lemon or lime zest. Sumac powder is very popular in the Middle East and is used in various dishes. It's not only used in savory dishes; it can be found in desserts, cocktails, and even used to make sumac lemonade!
In some recipes, sumac can be substituted with lemon zest or a pinch of citric acid. However, in a recipe like biwaz, it's a main ingredient and should not be substituted. 
No, you do not need to use red onions to make sumac onions. You can also use white onions and yellow onions to make marinated onions.
👩🏼🍳 Pro Tips
- Sumac loses its flavor if it's stored for any length of time. It's a good idea to keep sumac frozen until needed to retain its freshness. Especially if you don't use it too often.
- If you want to spice things up a bit, you can add some chili flakes to the marinated onions.
- Sumac marinated onions are good for up to a week or longer.
- Use leftover sumac onions in salads, mix them into rice, stir-fry, soup, and more!
🥩 More Middle Eastern Recipes
If you love biwaz, give these other Middle Eastern recipes a try!
📖 Recipe
Marinated Sumac Onions (Biwaz)
Ingredients
Equipment
Method
- Peel and slice the red onion into thin slices. Add onion slices to a bowl, along with the chopped parsley.
- Whisk lemon juice, vinegar, olive oil, sumac, salt, and sugar in a small bowl.
- Pour the sumac dressing over the onions and parsley, then whisk thoroughly to blend the ingredients.
- Allow the flavors to come together for an hour or so before serving with your favorite dishes!
Nutrition
Notes
- Sumac loses its flavor if it's stored for any length of time. It's a good idea to keep sumac frozen until needed to retain its freshness. Especially if you don't use it too often.
- If you want to spice things up a bit, you can add some chili flakes to the marinated onions.
- Sumac marinated onions are good for up to a week or longer.
- Use leftover sumac onions in salads, mix them into rice, stir-fry, soup, and more!
Patty says
Loved them. Will make again!
Hilda Sterner says
Thanks, Patty!
Megan says
So I love sumac onions and was jazzed to find this recipe! I didn't get everything out of the cabinets first and to my surprise I poured out and poured in 1tablespoon of balsamic vinegar (I buy the same bottle brand red wine vinegar and considering changing that now). I finished with the rest of the red wine vinegar and omitted the sugar in the place of balsamic and by golly it was good! Only (unintentional) change and loved it. Probably good for those easing I to the taste the more I think of it. I've made a proper batch too and over the moon with the recipe - thank you so much !!
Hilda Sterner says
Hi Megan,
Thank you so much for your review and your great suggestion. I will have to give that a try when I make my next batch. Thanks for sharing the information with my readers too!
Richard says
I just bought a jar of sumac, how can I tell if it's still good? It's not as tart as I thought it would be, with a kind of earthy taste. Does that sound right?
Hilda Sterner says
It does have an earthy flavor, so that sounds right. If it's no longer good it will have an unpleasant aroma.
Faythe says
I will try this recipe with grilled lamb chops! I love sumac, red onions and fresh parsley so this recipe will definitely fit into my autoimmune/leaky gut diet cookbook. I will also try adding cucumbers.
Thank you
Hilda Sterner says
Hi, Faythe, I bet it will be amazing with lamb chops!
Suzy says
This is absolutely delicious. I have used red onions and also shallots and can't get enough of it! Thank you!
Hilda Sterner says
Thank you, Suzy! I'm so glad you like them as much as I do!
Emilee says
We absolutely loved this recipe. We used these stop meatloaf sandwiches to bring a little excitement to an ordinary weeknight meal. I can imagine a thousand ways to use this recipe. Thanks!
Hilda Sterner says
Hi Emilee,
Thank you so much for the review. I agree, there are so many ways to use marinated sumac onions. I love your idea of including them in a sandwich, yum!
Kelly Methey says
This is an interesting sounding recipe. I love onions so I will be trying it, if I can find sumac powder. The only sumac I ever knew of was poison sumac as a kid growing up! Hahaha
HildaSterner says
I'll give you some if you don't want to buy it.;)