I love red onions because even just a few slivers of fresh red onion can truly transform a recipe (see Thai Curry Vegetable Soup and Slow Cooker Coconut Curry Lentils) and there’s no substitution that is really quite like it. BUT I can rarely find a red onion that is smaller than a softball and I usually only need 1/4 or less of it for a recipe. Because I hate to waste the rest of the onions, I always use the leftovers to make a batch of these Pickled Red Onions
What Are “Quick” Pickles?
There are two methods for pickling vegetables: through fermentation or by using a vinegar-based brine. Both methods use a salty and acidic liquid to prohibit the growth of dangerous bacteria. With fermentation, the acid is created by microorganisms, but this can take days or even weeks to accomplish. Store-bought vinegar creates this brine almost instantly, hence the name quick pickle.
The trade-off for this quick process is that quick pickles do not contain probiotics, like fermented pickles, and the flavor can be a little more one-dimensional. Fermented pickles are a bit more of an exact science and can take some practice to get right (here’s a recipe for Fermented Sour Pickles, if you’re interested), whereas quick pickles are pretty hard to mess up.
How to Use Pickled Red Onions
Pickled red onions are AWESOME on tacos, sandwiches, carnitas, salads, pizza, nachos, flatbread, avocado toast, burgers, and lots of other things (practically any Mexican dish). Instead of thinking of these pickled red onions as a substitute for fresh red onions, think of them as a non-spicy alternative to pickled jalapeño. That tangy pickled flavor tastes great anywhere you’d normally use a pickled jalapeño.
How long do They Last?
Keep your pickled red onions refrigerated and in the brine and they’ll last 3-4 weeks in the refrigerator! The flavor gets better over time as the onions marinate in the brine. Just make sure to keep your pickled red onions refrigerated in a non-reactive, air-tight container, like a mason jar or other food-safe storage container.
Customize Your Onions
There are a million different ways to make pickled red onions, so I’ve provided a very basic version below. As you begin to make them more often, you can start to tweak the flavors to match your preferences. Experiment with the seasonings and spices by adding ingredients like bay leaf, star anise, sliced jalapeño, or red pepper flakes.
What Kind of Vinegar to Use for Pickled Red Onions
The recipe below uses white vinegar, but you can use different kinds of vinegar in your pickled red onion recipe to change the flavor. I suggest not using vinegar with strong flavors so they don’t overpower the onions or the other ingredients. Try using rice vinegar, white wine vinegar, red wine vinegar, or apple cider vinegar in your pickled red onions!
(Tacos made with Chili Rubbed Pulled Pork, fresh jalapeño, pickled red onion, and cotija.)
Pickled Red Onions
Servings 10 1.5 cups totalIngredients
- 1.5 cups sliced red onion ($0.32)
- 1 clove garlic ($0.08)
- 3 Tbsp white sugar ($0.06)
- 1.5 Tbsp salt ($0.15)
- 1/2 tsp peppercorns ($0.05)
- 1 cup white vinegar ($0.06)
Instructions
- Thinly slice the red onion into 1/8-inch slices. Peel the garlic. Place the onion and garlic in a large glass or ceramic bowl.
- Add the sugar, salt, and peppercorns to a small sauce pot. Add the vinegar and stir until the sugar and salt are dissolved. Place a lid on the pot and bring the mixture up to a boil over medium-high heat.
- When it reaches a boil, pour the vinegar over the sliced onion and garlic.* Press the onion down so all the pieces are submerged, then let the mixture cool to room temperature. I sometimes place a piece of plastic wrap over the onions to help push and hold them below the surface of the brine (see step by step photos below).
- Once cool, use the onions immediately or transfer the onions and all the brine to a covered non-reactive container (glass, ceramic, or plastic) for storage in the refrigerator. The onions can be stored in the refrigerator for 3-4 weeks.
See how we calculate recipe costs here.
Notes
Nutrition
How to Make Pickled Red Onions – Step by Step Photos
This recipe works for up to about 2 cups of sliced red onion, but you can use less if you have less. It’s great for using up a leftover half onion, but I’ve used a whole onion for demonstration purposes here. Slice the onion into ⅛-inch slices.
Place the sliced onions and one clove of peeled garlic in a large ceramic or glass bowl.
Add 1.5 Tbsp salt, 3 Tbsp sugar, ½ tsp whole peppercorns, and 1 cup white vinegar to a saucepot. Stir to dissolve as much of the salt and sugar as possible. Place a lid on the pot and bring it up to a boil over medium-high heat.
Carefully pour the boiling vinegar brine over the sliced onions and garlic in the bowl. Stir to combine and press the onions below the brine. Allow the mixture to come to room temperature. I like to take a piece of plastic wrap and press it down onto the onions to help them stay below the brine just as soon as it’s cool enough to touch.
As the onions soak in the brine they’ll begin to turn an incredibly vibrant shade of pink. The pigment in red onions and red cabbage is a natural pH indicator. Don’t you just love food science??
Once the onions have come to room temperature and are a vibrant pink color, transfer them to an air-tight food storage container and refrigerate until ready to eat, or up to 4 weeks. The flavor gets even better after a few days!
(Tacos made with Chili Rubbed Pulled Pork, fresh jalapeño, pickled red onion, and cotija.)
1/2 teaspoon of peppercorns? I’m your photo it looks like way more than that? Anyway, thank you for the very simple recipe!
Plan on trying this it sure sounds good. Thanks.
Red onion recipe sounds easy enough and I love red onions and they are so healthy – I’ll try to make some soon
Can I use Vandalia onion instead?
I have not heard of vandalia onions. Are you referring to vidalia? If so, yes you can pickle vidalia onions. However, they are much sweeter that red onions and the amount of sugar in the recipe should be decreased. As we have not tested it, we cannot give you guidance,
1st time, easy to follow, great results thanks
Do I take the onions out of the brine before storing in the refrigerator?
No. Keep them in the brine so they don’t dry out. xoxo
I’ve made lots of pickled red onion recipes, (I’m sort of a pickled red onion connoisseur 😉) and this one is the best & the easiest!
These are meal transforming! I started a second batch the moment we got low on the first batch. Used on pizza, tacos, salads, and more. Thank you!
Incredible. We didn’t realize how much we needed pickled red onions until we came across this recipe a few years ago and made these as a side that called for them. Now they’re a staple. We always have some in the fridge. Goes great w tacos, any Mexican food, on sandwiches, etc. When I bring them places someone always comments on how good they are.
The only altercation, I add a little dill. I buy a couple huge dill plants from farmers market and pull off the usable dill and throw it in freezer, then grab a bit when making these and throw them in with the onions. Either way, amazing recipe thank you!
What can I use in place of peppercorns if I don’t have any?
Coriander Seeds or fennel Seeds. If you don’t have those, don’t worry about it. It will still turn out great. You can also add a dash of ground pepper to the mix.
These are easy and perfect! My family loves them-and my 15 year old daughter eats them right out of the jar! Thank you for the recipe!
This was a nice recipe. I’ve pickled various veggies for Thai dishes, etc so I understand there’s a balance between salty & sweet. The salt in this seemed overwhelming. I’ll use it again reducing to 1.5 tsp salt. I liked the black peppercorn in it. We put them on bbq pork tacos. Thanks.
Just perfection! These pair so well with so many different styles and types of food. Tacos, salads, Greek pitas, Italian sandwiches, you name it.
I made this recipe twice and the flavors are great — especially on the second day of fermenting in the fridge. The second time, I used red wine vinegar, instead of white, and I found the flavor to be even better. The onions go great with any beef dish, especially london broil. I tried pairing the pickled onions with a side of red wine/butter sauteed mushrooms and found the combo to be a keeper in our household. Thanks for another go-to recipe!
Is it possible to safely reduce the salt? I’m on a low sodium diet. Obviously I’m not going to eat the entire bowl of onions in once sitting but I’d still like to use a bit less–maybe one tsp total.
I just Googled it and found this document from Colorado State University that says, “A few low-sodium, high-vinegar,
fresh-pack pickle recipes have been developed. Any fresh-pack pickle recipe that calls for as much or more vinegar than water and provides a finished product with at least 1/4 cup of 5 percent acid vinegar per pint jar of pickled products can be safely made without salt. Sweet pickles generally taste better without salt than dill pickles. If salt is omitted from fresh-pack dill pickles, try adding hot peppers, herbs and garlic instead. Dill pickles taste better if as little as 0.5 percent salt by weight of entire contents is added. This is the equivalent of 1/2 to 3/4 teaspoon of salt per pint jar of pickles.” The key here is “fresh pack” which means it must be refrigerated, unlike fermented pickles. I hope that helps!