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.)
I’ve made this recipe several times resulting in perfect pickled onions! I put them on everything, but they are so good I could just eat them straight out of the bowl. I love garlic, so I slice or mince it to get more garlicky flavour.
I used this recipe and my onions came out perfect 👌 thank you for sharing! Note I have a question, can I reuse the brine to make more onions or should I make a fresh batch?
I’m not sure about that! I’ve honestly never tried. :) I’m not sure about any possible food safety issues surrounding that, either, so you may want to do some Googling.
Can you make them without sugar? Type 2 diabetic who loves onions here.
I don’t suggest it. The sugar is really important for balancing the flavor of all that vinegar.
Great recipe! I use them on nachos, smashed potatoes and other appetizers. My hubby eats them till we are out and asks for some more ⭐️⭐️⭐️⭐️⭐️
Since we are on that subject … Beth, do you have a recipe for Indian style onions or chutney? Thank you
what size jar do you need for this many onions?
Probably a 16oz. jar.
I love pickled onions! My husband likes onions, but isn’t a fan of red onions, do you think I could substitute any other onions?
I’ve had them with white onions.
Delicious! I have made these a few times now
cannot have our usual dinner salad without itty bitty pieces red onion. also have pickled thin cuke slices with the onions.
These are a GAME CHANGER. Now I can’t eat any sort of rice/bean bowl without them! They are so easy and they add so much to a dish!
These are great, but the nutrition info say 215 cal? I think there’s an error somewhere.
Holy moly!
I have made pickled onions since my mother taught me how to do it. But I never used garlic and pepper before and I have to say I really loved it. Thank you!
It said to put in the refrigerator after picking do you have to put in refrigerator???
Yes they will get softer quicker and turn faster if you don’t refrigerate. This recipe isn’t for long term storage.
These are awesome they lasted 1 week if that. I tweaked mine a little I added jalapeno slices some seasoned rice vinegar to the 1 cup of vinegar & substituted 2 Tbsp of sugar for Monkfruit & a little less salt bcuz of the seasoned vinegar. We liked it so much we’ve eaten it straight from the jar. Thank you so much for this recipe.
Amazing! So easy and tasty. Better than anything store bought
These were outstanding and super easy. I enjoyed them for several weeks on tacos, tostadas, veggie burgers, and salads. I will definitely be making them regularly. Thank you!
Super easy, my crew loved these! Will make again.
Do I use table salt or kosher salt? There is never a description of what kind of salt to use. It makes a huge difference
I prefer kosher salt when I make these, but if table is what you have on hand it will work just fine.
Love these! They didn’t last long in the fridge – we put them on so many things. Can the brine be reused?
I can’t keep them long enough in my house either! I wouldn’t recommend reusing the brine.
Don’t reuse the brine for pickling more onions, but it works nicely to add an oniony/acidic flavour to sauces.