The Only 5-Ingredient Pickled Red Onions Recipe You'll Ever Need

Read the recipe once and you'll never forget it.

3-ingredient pickled red onions

Simply Recipes / Ockra

Pickling red onions helped me get over my fear of pickling. My abstract idea of pickling involved heavy-duty cookware and a razor-thin line between "preserved" and "this Mason jar is in no way properly sealed." Like I imagine many of you reading this now, pickling seemed like something I needed intimate knowledge and years of experience to do well.

But it seems that, despite the fear, many people recognize the transformative power of pickled red onions—and are hungry to try them out at home right now. For a little Simply Recipes #bts: one of our editors sent a message to the group on Slack notifying us that search engine traffic for "how to make pickled onions" is at a 10-year high this month. 

We scoured TikTok and other social media platforms to see if something was happening with onions. We could find no evidence of anything unusual, so we came to the only logical conclusion: everyone collectively remembered that pickled onions are delicious and decided they belong on everything. 

pickled red onions in a fish sandwich

Simply Recipes / Sally Vargas

Why Pickle Red Onions? 

You can pickle any onion, but red onions tend to be less sharp in flavor—which is why you see red onions used often when a recipe calls for raw onion—and their color can't be beat. 

Pickling red onions is almost like a magic trick: they go from a beautiful purple color to a vibrant magenta, adding a pop of color to dishes you can't get with many other foods. But if you're jonesing for pickled onions, you can try pickling any onions you have on hand. 

Fingerling potatoes with pickled red onions

Simply Recipes / Elise Bauer

How To Make the Easiest Pickled Red Onions Ever

You don't need anything fancy to pickle red onions: you likely have all the tools you'll need in your kitchen right now. Pickled red onions need no fancy preservation step and can be ready in minutes. 

You'll need:

  • 1 cup water 
  • 1 red onion
  • 1 cup apple cider vinegar
  • 1 teaspoon salt
  • 1 teaspoon sugar

Bring the water to a boil. 

Meanwhile, slice your onion in half through the root, then in half-moon shapes. If you have a mandoline, this is the perfect time to use it. Put the onions in a non-reactive container like a Mason jar or something made of glass. 

Add the vinegar, salt, and sugar over the onions. Then add the boiling water (you might need to pour a little extra water to submerge the onions completely—that's fine). Let the mixture cool to room temperature, then cover and stash in the fridge. 

The onions should be ready to eat in about an hour and will last two to three weeks, but if you notice any off smells or cloudiness in the jar, throw them out. 

I Tested Different Ratios—I Like This Recipe Best

As I wrote this story, I wanted to see what other recipes people used for their pickled red onions, and I saw recipes omit the salt, double the sugar, or use a heavier dose of vinegar to get a sharper flavor. So I tried four pickled onion preparations and changed one variable in each batch. For example, I added two teaspoons of salt instead of one for one batch and two teaspoons of sugar in another. All of these riffs were great—slightly different but still delicious. 

I liked the recipe that kept all the ratios the same (same amount of water to vinegar and salt to sugar—one measurement of each), but you can experiment with these ratios and see which you like best.  

Pickled Red Onions in Sandwich

Simply Recipes / Garrett McCord

Riffs on Pickled Red Onions

  • I like to use apple cider vinegar, mostly because I like the flavor, and it's the vinegar I use most in my kitchen. Apple cider vinegar tends to be milder in taste, but you can use other kinds of vinegar, like distilled white vinegar, rice vinegar, and white wine vinegar. The only type of vinegar to avoid is balsamic and malt vinegar. 
  • You can add other ingredients to your pickling brine to change the flavor! Consider adding dried chilis, cumin seeds, or peppercorns. 
  • Cutting the onion into a half-moon shape is fun but not required. You can leave the onion in rings or give the onions a rough chop—totally up to you! 
  • This guide lends itself well to doubling, halving, or making whatever quantity of pickled onions you'd like.

How To Serve Pickled Red Onions

  • On a sandwich to give extra tang and crunch! 
  • In a grain bowl
  • Thrown onto a pizza
  • As a condiment for tacos
  • In a salad 
  • Anywhere! Truly, the options are endless!