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.
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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.)
Nice recipe.
By the way if you need to save part of an onion, first cut away the needed amount before peeling. Cover the remaining half tightly with saran wrap, and tighten it at the part where there is till skin. It will stay fresh in the fridge for days.
Just finished making them, but when I went to try them, they were deathly salty, even when I reduced the amount of salt to just 1 TBSP.
Maybe a pinch of salt would be sufficient for future references. The color was really pretty though!
I just made these pickle onions today. I just don’t know when they will be ready to eat. I know it says you can store them for 3 to 4 weeks.
You can eat them as soon as the recipe is finished. :)
Used Kosher salt, would cut the salt in half, way too salty. I added a cup of water to the brine also, one medium red onion yields more than 1.5 cups. Nice simple recipe.
Really delicous— I highly recommend these on salads. So much flavor!
Can you can and store these? Like canned pickles.
I’m not sure, I am not experienced with canning. :)
Thank you, Beth! You rock!
I’ve been searching for a basic recipe for a full week since I decided that assorted refrigerator pickles be amazing as last minute Christmas gifts. I used to make a lot of them but lost the recipe. Doing this later today and probably using the same brine with different spices on my mixed veggie jars (I have carrots, cucumbers, green beans, yellow onion, and cauliflower to mix or isolate as I choose).
The onions are ready, and they are AMAZING!!!
The only reason I’m giving four instead of five stars is the ingredient list not being clear enough. On a related note, I think I figured out why people had a problem with the saltiness. 1.5 tablespoons of table salt is much more potent than 1.5 tablespoons of pickling or kosher salt.
What are your thoughts on using different types of vinegars? I read on other recipes that white vinegar might be too harsh and it’s better to use other vinegars such as white wine vinegar.
I think I’d stick to clear vinegars or vinegars that are not strongly flavored. So I think rice vinegar would work very well, but I definitely wouldn’t use something like balsamic.
These are so simple and this is just a perfect recipe. They perfectly compliment the barbacoa tacos I recently learned to make. They’re delicious on sandwiches too and I’m sure so many other applications. My loved ones were so impressed to have these with out meal. Thank you!
I wonder if yoy couldn’t do something to preserve this. Sounds similar to my normal pickle, and sauerkraut recipe. Only I leave it unrefrigerated for a month to ferment. Have to get the right amount of salt though.
the amount of salt is 3% by weight of the onions.
So the garlic does not need to be minced or cut? Should it be removed when storing the onions?
It doesn’t need to be minced or cut, but you could if you prefer. I leave the garlic clove in the brine whole while storing the onions and the flavor continues to steep. :)
Garlic should always be chopped the release the benefits of garlic.
But what is the batch size for this recipe?
Hey- I can’t wait to try these, I have been searching for a recipe. I went to a cafe and ordered this amazing Bagel vegetarian sandwich and they put these pickled onions on it and it tasted heavenly. Since before that, I never knew recipes that could use these. Question for you, Can these be put in the freezer? I am thinking about making a big batch to store and have on hand when I need them without having to make them the night before. Any tips?
Honestly, I’m not sure! :P I’ve never tried to freeze anything like this. I wonder if the liquid would freeze solid or if it would stay kind of slushy like high concentration solutions that don’t have a lot of water.
Hi Nikki, You could certainly try it. I’d recommend without the liquid and maybe after some days in the fridge so they’re well seasoned.
Lay them on a sheet, probably covered in parchment for noon stick (don’t use metal that isn’t covered) and freeze, then put in container for use.
I use frozen fresh onions all the time in cooking. The caution I’d give you is that the onions cell wall will probably break down in the freezing as the water expands so they’ll not be crisp upon thaw. I hope it works for you.
Great suggestions Andrea! Thanks!
Could you reuse the pickle juice and just keep adding red onions to the mixture once you are done?
I think you’d probably want to use fresh. The onions may absorb sugar, salt, and moisture at different rates from the brine.
My absolute favorite go-to pickled onion recipe! I have made this time and time again, and never stray from the recipe. Perfect as is. Even my picky eaters love these :)