Pickled Onion

5 from 1 vote
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Everyone loves this obsessively-good pickled onion recipe that transforms simple red onions into a beautiful, tasty garnish. Try this easy method and you’ll be making quick pickles all the time.

Pickled onions in a small glass bowl with a fork on top.

Why Do Pickled Onions Taste So Good?

Pickled onions taste so good because of a delightful combination of food science and a balance of flavors:

  1. Acidity & Brightness: The vinegar used in pickling provides acidity. Acidic foods can stimulate the taste buds and bring brightness to dishes, cutting through rich, heavy flavors and refreshing the palate.
  2. Sweet & Salty Balance: The sugar and salt used in pickling brine create a balance. Our taste buds inherently enjoy this harmonious play between sweetness and saltiness, making the pickled onions not only tangy but also slightly sweet and salty.
  3. Crunchy Texture: The process of pickling, when done right, can preserve the crunchiness of the onion, which contrasts well with softer dishes. This contrast in texture adds to the overall sensory enjoyment.
  4. Umami Enhancement: Onions naturally contain glutamate, a compound responsible for the umami flavor, which is often described as savory. The pickling process can sometimes enhance this inherent umami taste, making pickled onions even more delicious.
  5. Contrast with Other Dishes: Pickled onions often taste especially good because they’re paired with foods that benefit from their tangy contrast, like heavy meats, rich cheeses, or fatty foods.

In short, pickled onions are a fantastic example of how simple ingredients and processes can come together to create something that delights multiple senses at once.

Gather Your Ingredients to Make This Easy Pickled Onion Recipe

Diving into this pickled red onions recipe requires only a few simple ingredients. Let’s get a closer look:

  • Red onion: The star of the show, adding crunch and tangy sweetness.
  • White vinegar: Provides the acidic medium, giving that classic pickled tang. Swap with apple cider vinegar if you fancy a mellower, fruity note.
  • Water: Helps dilute the vinegar, ensuring the onions aren’t overly sour.
  • Sugar: Balances the acidity and adds a hint of sweetness to the mix.
  • Salt: Enhances flavors and preserves the onions, ensuring they stay crisp and flavorful.
Ingredients for pickled onions, including salt, sugar, red onion, and white vinegar.

Variations and Substitutions

Here’s how you can play around with these pickled onions to suit your palate:

  • Spice it up: Add a few slices of jalapeño or a pinch of red pepper flakes for an extra kick. You can also add a couple of whole garlic cloves, mustard seed, or dried or fresh herbs like oregano, thyme or bay leaf.
  • Sweetener swaps: Substitute sugar with honey or maple syrup for a nuanced sweetness.
  • Zesty flare: A bit of citrus zest, whether from lemons or oranges, can introduce a fresh tanginess.
  • White onions: swap the red onion for white onion if you like.

Grab these Tools

Prepping a batch of this pickled red onion recipe couldn’t be easier.

  • Mandoline slicer: For perfectly thin, uniform onion slices. If you don’t have one, a sharp knife will work too.
  • Small saucepan: Essential for heating your pickling liquid and dissolving sugar and salt.
  • Airtight mason jar or container: To store the pickled onions. Glass mason jars work wonderfully. Whatever you choose, just make sure it has a tight-fitting lid.

How to Make Pickled Onion: Easy Step-By-Step Directions

Here’s how you can transform a humble red onion into a zesty accompaniment:

Red onions, sliced thinly. A saucepan with a mixture of vinegar, water, sugar, and salt, simmered until dissolved, then cooled for a few minutes.
  • Prepare the raw onions: Begin by getting those perfect, thin slices. A mandoline slicer can be your best friend here.
  • Make the vinegar mixture: Heat the vinegar, water, sugar, and salt. This is where the magic begins, melding flavors together.
  • Jar the onion: Neatly place your sliced onion in your chosen container, awaiting its flavor transformation.
  • Add the liquid: Pour the just-warm mixture over the onions, ensuring they’re fully submerged for an even pickling.
  • Cool and store: Give your onions a moment to relax at room temperature, then tuck them into the fridge for their flavor infusion.
  • Patience is key: Wait at least an hour, but for the best punch of flavor, let those onions soak overnight. Your taste buds will thank you later.
Thinly sliced red onions in a jar. Warm pickling liquid poured over the onions, ensuring they're fully submerged. Left to cool for 15-30 minutes at room temperature, then covered and refrigerated.

Pickled Onion Make Ahead and Storage Tips

Keep your pickled onions in top condition with these guidelines:

  • Cooling is key: Ensure the pickling liquid has cooled a bit before pouring over the onions. This keeps them crunchy.
  • Longer, the better: While an hour is the minimum optimal time to wait, letting them sit for a day or two will enhance the flavors.
  • Airtight always: Use a jar with a tight-sealing lid to keep any unwanted fridge flavors at bay.
  • Shelf life: When stored correctly, pickled onions can last for 2 weeks in the refrigerator.

Final Notes, Tips and Food Science Secrets

Dive into the science of quick pickling with these expert insights to perfect your quick pickles:

  • Osmosis in action: The salt in the pickling solution draws out the moisture from the onions through osmosis, enhancing their crunchiness.
  • Vinegar’s role: The acidity of vinegar not only flavors the onions but also creates an environment where harmful bacteria can’t thrive, preserving the onions.
  • Thin slices matter: Cutting your onions thinly allows for a quicker and more uniform pickling process. A mandoline slicer is the best way, but a sharp knife does the trick.
  • Balancing act: If your pickling solution tastes too tart, balance it with a bit more sugar. The sugar doesn’t just sweeten; it complements and counterbalances the vinegar’s acidity.
  • Avoid metal: Using non-reactive utensils and containers like glass or plastic ensures there’s no metallic taste in your pickled goods.
Thinly sliced red onions on a wooden chopping board with a mandoline slicer nearby.

How to Serve This Quick Pickled Onions Recipe

I use up this quick pickled red onions recipe to finish so many delicious savory recipes, like:

  • Mexican topper: Brighten up your tacos with a generous sprinkle of pickled onions. I love them with baja fish tacos, chicken tacos, or these fish tacos with cabbage slaw especially. They’re also delicious on other Mexican recipes, like tostadas, cheese quesadillas, chili con carne and walking taco casserole.
  • Burger booster: Layer them on your burgers for an added layer of flavor and a delightful crunch. Perfect with my ultra-juicy ground chicken burgers.
  • Salad spinner: Mix into salads to introduce a tangy element and a vibrant color contrast.
  • Avocado toast twist Top your morning toast with mashed avocado, a sliced microwave-boiled egg, and a sprinkle of pickled onions.
  • Cheeseboard champ: Pair with cheeses, especially strong ones like blue or feta, for a palate-cleansing counterpoint.
Two delicious Baja fish tacos artfully presented on parchment paper, drizzled with flavorful Baja sauce and accompanied by a bed of crispy cabbage slaw and pickled onions.


Got some burning pickled onion questions? Don’t worry, I’ve got you covered!

What are pickled onions made of?

Pickled onions are made of thinly sliced onions marinated in a mixture of vinegar, water, sugar, and salt.

Can I use other types of onions for this recipe?

Yes, while red onions are popular for their vibrant color, you can use white or yellow onions. The taste might be slightly different, but they’ll still be delicious!

Can I use different types of vinegar?

Certainly! While the recipe suggests apple cider vinegar, you can experiment with white wine vinegar, red wine vinegar, or rice vinegar for varied flavors.

Why is my pickling solution cloudy?

A cloudy solution is often due to the minerals in the water. It’s safe to eat, but if you want a clearer brine, consider using distilled water.

What can I use pickled onions for?

Pickled onions are a versatile condiment that adds a tangy and slightly sweet flavor to many dishes. You can use them as a topping for burgers, sandwiches, tacos, salads, or even as a garnish for grilled meats and seafood. They also make a great addition to charcuterie boards.

Are pickled onions probiotics?

This pickling method uses vinegar, which creates an environment where most bacteria (including probiotics) can’t thrive. For probiotic benefits, consider fermenting onions using a saltwater brine without vinegar.

How long can I store pickled onions in the refrigerator?

Pickled onions, when stored in an airtight container, can last for 2-3 weeks. Make sure the onions remain submerged in the pickling liquid.

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5 from 1 vote

Pickled Onion

Transform humble onions into a show-stopping garnish. Everyone loves this obsessively-tasty pickled onion recipe. Click to unveil the secret!
Prep Time: 10 minutes
Total Time: 10 minutes
Servings: 8


  • 1 medium red onion
  • ½ cup white vinegar or apple cider vinegar, if you like the flavor
  • ½ cup water
  • 1 tablespoons sugar
  • 1 teaspoon salt
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  • Peel the red onion and slice it thinly. You can use a knife or a mandoline slicer for even, thin slices.
  • In a small saucepan, combine the white vinegar, water, sugar and salt. Bring the mixture to a simmer over medium heat, stirring until the sugar and salt have dissolved. Remove the pan from heat and let the mixture cool for a few minutes.
  • Place the sliced red onion in a clean jar or airtight container.
  • Pour the warm pickling liquid over the sliced onions, making sure they are fully submerged. If needed, use a spoon to press the onions down. The pickling liquid should cover the onions completely.
  • Let the pickled onions cool at room temperature for about 15-30 minutes. Then, cover the jar or container and place it in the refrigerator.
  • Allow the pickled onions to marinate in the refrigerator for at least 1 hour, but preferably overnight. The longer they sit, the more the flavors will develop.



The pickled onions can be stored in the refrigerator for up to two weeks.
Pickled onions are a versatile condiment that can add a tangy and flavorful punch to various dishes, such as sandwiches, salads, tacos, burgers, and more. Enjoy!


Calories: 18kcal | Carbohydrates: 4g | Protein: 0.2g | Fat: 0.03g | Saturated Fat: 0.01g | Polyunsaturated Fat: 0.01g | Monounsaturated Fat: 0.01g | Sodium: 292mg | Potassium: 31mg | Fiber: 0.3g | Sugar: 3g | Vitamin A: 55IU | Vitamin C: 2mg | Calcium: 5mg | Iron: 0.1mg

Nutrition information is automatically calculated, so should only be used as an approximation.

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1 Comment

  1. LizJ says:

    5 stars
    OBSESSED with these pickled onions. So easy and so yum. I’ve been putting them on everything.