Easy Pickled Red Onions Recipe

Learning how to make pickled red onions is SO easy – it only takes five minutes and you probably have all the ingredients! You’ll love having a jar of these in your fridge for tacos, avocado toast, and more!

If you follow me on Instagram, you probably already know from my stories that I’m obsessed with these. OBSESSED. As in three meals a day obsessed.

PS: If you don’t follow me on Instagram, consider hopping over and checking it out! You’ll see some behind-the-scenes stuff on my stories!

The first time I made pickled red onions was for my daughter’s birthday party right after we moved into our new house (seriously, two weeks after). We did a taco bar with all the fixings. I made Cheesy Baked Corn with Bacon and Jalapeño, Homemade Refried Beans, Cilantro Lime Rice, from-scratch Margaritas, and two kinds of salsa: Restaurant Style Salsa and Chipotle Salsa. And of course guacamole!

On a whim, I decided to make pickled red onions. They are great on almost any Mexican dish and tacos are no exception. I was amazed at how quickly they disappeared! Faster than the cheese! Not faster than the margaritas though.

Now when you open my fridge, you’ll often see a jar of pickled onions right alongside the salsa, ketchup and mustard. Once you learn how to make them, I bet they’ll always be in your fridge, too.

About Pickled Red Onions

I’ll run through the process here and give you lots of extra tips and variations. As always, if you prefer, click to the recipe card which has complete directions and nutrition information.

What You’ll Need

• Red Onion: Does it have to be a red onion? No, not necessarily, but a red onion has such a beautiful color, don’t you think? Other types of onion are just fine though.
• Apple Cider Vinegar: While you can use other types of vinegar, my preference is always apple cider vinegar. I typically have it on hand and I like the subtle sweetness it adds. White wine vinegar, rice vinegar, or plain white vinegar are good substitutes. Use a mixture of two kinds if you like. Balsamic vinegar is not a good choice for this recipe.
• Sugar: Start with a tablespoon and adjust as desired. Some of us like things a little more tart and others a little sweeter. That’s why homemade is the best — you can make everything just the way YOU like it. In fact, if you’d rather, substitute honey or maple syrup for the sugar.
• Salt: Most pickles have a bit of salt. It just makes them taste better. We use kosher salt but other varieties work as well.
• Very Warm Water: The water dilutes the vinegar so it’s not so in-your-face tart. Heating it helps to dissolve the sugar and salt.
• Jar or Bowl: I prefer a jar because it’s easier to store in the fridge, but a covered bowl is fine, too. Don’t feel like you have to run out and buy a jar. Recycled jars with a tight-fitting lid work perfectly. Just make sure it’s nice and clean.

How to Make Pickled Red Onions

It’s so easy, folks! No pans, no cooking, and only one measuring cup to wash.

Slice the red onions as thin as you like. I use a mandoline to slice the onions. This is the mandoline I have. Not only does it get them super thin, it also gets the job done more quickly than you would think possible. However, please do watch your fingers! No one wants pickled fingertips in the jar.

Can you make pickled red onions without a mandoline?

Absolutely! You’ll need a sharp knife, a cutting board, and a steady hand. Slice the onions as thinly as you can.

Here’s another thing to think about though. Some folks like the onions sliced a little thicker. The thicker slices stay a bit crisper. You’ll want to allow a little extra time for them to soak in the brine before eating them.

Okay, enough about slicing. Stuff all the sliced onions in a (very clean) jar of your choice. Nothing fancy here, no special layering or anything, just pile them in. If they don’t fit in one jar, use two jars. I chose these fancy little jars for the photos but most of the time I use a larger jar.

In a measuring cup, stir together the apple cider vinegar, salt, sugar, and warm water. Stir until the sugar and salt are dissolved.

Pour the pickling mixture over your sliced onions.

There should be enough liquid to completely cover the onions. If there isn’t, either remove some of the onions, use a smaller jar, or make more pickling brine. If it’s super close, just add in a little more water or vinegar to top it off.

Let them set on the counter for an hour, uncovered, to cool off and absorb the flavorful brine. At this point, you can begin to enjoy them but if you’re making them ahead, cover them and stick them in the fridge. They’ll keep in the fridge for two to three weeks (but they probably won’t stick around that long)!

FAQs

Make It Your Own

There are lots of variations you can make to this recipe.

• Use a different type of onion or slice it thicker. Slice the onion into rings, half moons, or roughly chop it.
• Substitute a different kind of vinegar, or another sweetener.
• Make the onions sweeter or not as sweet.
• Add red pepper flakes if you like things spicy.
• Sliced garlic cloves add pungent flavor.
• Try adding whole spices (peppercorns, fennel seeds, cumin seeds, mustard seed), a bay leaf, or sprigs of fresh herbs.
• Double the recipe or halve the recipe.

It’s easy to make it your own!

Storage Tips

Like I mentioned above, pickled onions will keep in the fridge for up to three weeks.

Can you freeze pickled onions?

I’ve never tried freezing pickled onions because they are so easy to make fresh. However, if you have a lot of onions that you’d like to use up, slice the onions and put the sliced onions in freezer safe bags. There’s no need for blanching. They’ll keep for about three months. When you’d like to make pickled onions, simply add the brine to the thawed onions and proceed with the recipe. They may not be quite as crisp.

More ways to Use Pickled Red onions

I gave you a bunch of ideas already but I have lots more!

• Fish Tacos (you’ll love these!)
• Vegan Tacos with roasted carrots, mushrooms, and quinoa
• Instant Pot Pulled Pork
• Instant Pot Carnitas
• Sheet Pan Breakfast Tostadas
• The Best Cauliflower Nachos
• Crispy Sweet Potato Tacos (the sweet potatoes are marinated in beer!)
• Grilled Pizza with arugula pesto
• California Breakfast Wrap
• BBQ Chicken Sweet Potato Nachos