There's nothing quite like the taste of sweet pickled onions - crunchy but not pungent, and great as a taco topper. I love pickling onions and adding them to everything!

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💭 Why you'll love this recipe
- Sweet and spicy: Onions when pickled, take on a really sweet taste and when pickled in a liquid with some red pepper flakes, provide the perfect complement of flavors!
- Super easy to make: This recipe comes together in literally 15 minutes, and needs basic ingredients you probably have at home.
- SO versatile: I love adding sweet pickled onions to everything - Tacos? Check. Grain bowls? Check. Sandwiches? Check. Eat them raw? You bet.
📋 Ingredients and notes
You'll need a red onion, a cup of distilled white vinegar, salt, sugar, garlic cloves and some red pepper flakes (if you choose to make it spicy!)
Notes and Variations
- Adjust seasoning: This is a simple pickled onion recipe, but you can also adjust the seasoning if you want to make it more spicy, more sweet (e.g. by adding cinnamon sticks) or use other warm spices in the pickling liquid!
- Works with other onions: I've used red onions here because it provides the sweetest flavors for pickling, but this recipe works great with whatever onions you have on hand. And if you're interested in other types of pickled onions - check out my Mexican pickled onions (with just four ingredients!), my pickled white onions, or pickled shallots!
📖 Step-by-step instructions
Slice the onions thinly and place in a jar
You'll want your onions sliced quite thinly, so I suggest using a sharp Chef's knife or a Mandoline slicer for this step. You can either slice it in whole circles, or chop the onion into halves, and then slice those pieces.
Place these onions along with two to three cloves of garlic, and some red pepper flakes in a large enough jar (you'll want enough space so the liquid can cover all the onions)
Prepare the pickling liquid and pour into jar
In a small sauce pan, add vinegar, equal parts water, salt, and sugar and heat until the sugar and salt fully dissolve in the liquid. Then, pour this liquid into the jar with onions. Let it sit uncovered until the brine cools down.
Give it all a quick stir and toss it in the fridge
Ideally, I recommend placing this in the fridge for about an hour or two, but make sure to chill at least 30 minutes before serving. Your quick pickled sweet onions are ready!
👩🏽🍳Top tips and FAQs
The pickled onions will last in refrigerator, in an airtight container, somewhere between two to three weeks. The longer you leave them in the fridge, the stronger the pickling effect!
I typically use simple white distilled vinegar to keep the recipe easy. However, any type of acid should work - so you can substitute with apple cider vinegar, or even lime juice (check out my Mexican quick pickled onions recipe!) Other types of vinegar (say, red or white wine vinegar) also work - but the flavor profile is different!
Oh, my word, everything! The most obvious answer is to use them as a taco topper (say, for my gochujang cauliflower tacos or fried avocado tacos) - but you can also use them in salads (for instance, my summer spinach and avocado salad). But my favorite? Add them to avocado toast. You simply won't go wrong!
🍴 Serving and storage suggestions
This recipe takes about an hour to make, assuming 45 minutes of chill time, and will last in your fridge for 2-3 weeks. Note that this has to be stored in an airtight jar or container in the fridge, and the recipe as written, is not meant for canning.
If you like this recipe, don't forget to try out my avocado pickle or jalapeno pickle recipe!
Did you make this recipe?! ⭐⭐⭐⭐⭐
Please leave a comment and a star rating and let me know how it went! We love hearing from you, thank you so much
📖 Recipe
Easy, Sweet Quick Pickled Onions
Ingredients
- 1 red onion, medium sized, sliced thinly
- 1 cup distilled white vinegar, can substitute with apple cider vinegar
- 1 cup water
- 3 tablespoons sugar
- 1 teaspoon kosher salt
- 2 cloves of garlic, can be minced or whole
- 1 teaspoon red pepper flakes, optional
Instructions
- Slice the onions as thinly as possible - I typically use sharp cuts on my knife or a mandoline slicer. Place garlic, red pepper flakes, and sliced onions in a jar with a tight fitting lid
- Add the vinegar, water, sugar, and salt in a small saucepan over low to medium heat and heat - keep stirring until the sugar and salt dissolve completely (this takes about 1-2 minutes depending on your stove).
- Pour this liquid into the jar with the onions, and let it cool down to room temperature (about 10 minutes) and then chill in the fridge, at least 30 minutes. Your pickled onions are ready to go!
This recipe was so easy, but yet so delicious. I have put the pickled onions on my street tacos and deli sandwiches. Will definitely be making this again.
These picked onions were just as fast as you said and they were even better the second day! I just threw the whole cloves in because you said I could and the flavor was perfect! Had them on tacos and on my lunch salad. Brightened it all up
These pickled onions are the best topper on salads, burgers, or the random bowls I throw together. They give everything a great flavor!