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!
Why you’ll love it: This no cook recipe is quick, easy, and keeps well in the fridge for up to three weeks.
How long it takes: 5 minutes to prep, 55 minutes to marinate.
Equipment you’ll need: sharp knife or mandoline, measuring cup, small jar
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 these easy no cook onions. Pickled red onions 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
Are tacos the only way to eat pickled onions? No way! You’ll find that they are an excellent topping for avocado toast. It really livens up the avocado toast and the tangy pickled red onions are the perfect contrast to the rich, creamy avocado.
For breakfast, try topping scrambled eggs or breakfast sandwiches with a forkful or two of pickled onions. They really jazz things up without being too oniony or strong flavored.
Oh, and pizza, too! I bet you can’t wait to get started!
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)!
Most types of vinegar can be used for pickling except for balsamic vinegar or malt vinegar. White distilled vinegar is popular because it’s clear and doesn’t add any color to the pickled vegetable. It has a good acidity and a tart flavor. Other good vinegars to use are cider vinegar, white wine vinegar or rice vinegar.
Since this is a quick pickle, boiling isn’t necessary. The hot water will dissolve the sugar and salt. Adding boiling liquid to the onions softens them, making them less crispy.
They won’t last long because you’ll be eating them right up! Seriously, they’ll keep in the fridge for up to three weeks. If they look mushy or cloudy, or have a bad odor, toss them out and make a fresh batch. Be sure to wash and rinse the jar thoroughly or run it through the dishwasher.
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!
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.
What To Put Pickled Red Onions On
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
- 1 red onion, thinly sliced (use a mandoline if you have one)
- 1/2 cup apple cider vinegar
- 1 tablespoon granulated sugar
- 1 1/2 teaspoons salt
- 1 cup hot water (not boiling)
- Slice the red onions as thin as you can. I use a mandoline but a sharp knife works well, too.
- Stuff all the red onions in the jar of your choice. A bowl works too but a jar is easier to store in the fridge.
- In a measuring cup, combine apple cider vinegar, salt, sugar, and warm water. Stir to dissolve the sugar and salt. Pour the pickling mixture over the sliced onions, making sure they are immersed in the liquid, and let them set for an hour.
- After an hour, cover and store in the fridge for up to three weeks.
- Other types of onions can be used instead of red onions.
- Substitute maple syrup or honey for the granulated sugar if desired. For sweeter pickled onions, use more sweetener, for tangy pickled onions, use less.
- If you prefer, substitute plain white distilled vinegar, rice vinegar, or white wine vinegar for the apple cider vinegar. A combination is fine, too.
- Recipe is easily doubled. Make sure you have enough clean jars with lids. Sliced onions should be completely immersed in vinegar solution.
This website provides approximate nutrition information for convenience and as a courtesy only. Nutrition data is gathered primarily from the USDA Food Composition Database, whenever available, or otherwise other online calculators.