Food Edition›Preserve›Mexican›Side›Quick Pickled Red Onions
40 minEasy
Mexican · Side

Quick Pickled Red Onions

Submerge thinly sliced red onions in a hot mixture of vinegar, salt, and sugar for a bright, crunchy condiment that cuts through heavy or fatty meals. Within thirty minutes, the harsh raw bite of the onion dissipates, leaving behind a vivid magenta crispness that keeps in the refrigerator for two weeks.

Total time
40 min
Hands-on
10 min
Difficulty
Easy
Before you start

The acid matters as much as the onion.

Use a mandoline if you have one to ensure uniform thinness, which allows the brine to penetrate instantly. If you slice by hand, keep the pieces consistent so they pickle at the same rate.

  • Mandoline or sharp chef's knife
  • Glass jar with a tight-fitting lid
  • Small saucepan
Ingredients

What goes in.

  • 1 largered onion, sliced into paper-thin half-moons
  • 1/2 cupapple cider vinegar
  • 1/2 cupwater
  • 1 tbspcane sugar
  • 1.5 tspkosher salt
The key technique

The heat does the heavy lifting

Heating the brine until the salt and sugar dissolve ensures they are fully integrated before they touch the onions, preventing grainy pockets of seasoning.

Step by step

The method.

  1. Prepare the onions

    Pack the sliced red onions tightly into a clean glass jar, pressing them down so they fill the space without too much air.

  2. Simmer the brine

    Combine the vinegar, water, sugar, and salt in a small saucepan over medium heat. Stir until the liquid is clear and the salt and sugar have vanished.

  3. Submerge

    Pour the hot liquid over the onions. Use a spoon to push the onions under the brine if they float to the surface.

  4. Cool and set

    Leave the jar uncovered on the counter until it reaches room temperature, then tighten the lid and move it to the refrigerator.

Variations

Other turns to take.

Spiced

Add a few black peppercorns, a smashed clove of garlic, or a sprig of fresh oregano to the jar before pouring the brine.

Heat

Toss a dried chili de arbol or a few slices of fresh jalapeño in with the onions for a slow, lingering burn.

Tips & troubleshooting

When it doesn't go to plan.

Tip

If you want to remove some of the sharp sulfurous edge before pickling, blanch the sliced onions in boiling water for 15 seconds and drain well first.

Tip

The onions will turn a translucent neon pink within an hour; this is the sign that the acid has successfully penetrated the cell walls.

Tip

Do not discard the brine once the onions are gone; use the remaining liquid as a base for salad dressings or vinaigrettes.

Questions

The ones that keep coming up.

Why did my onions turn blue or green?

This is a natural reaction between the sulfur compounds in the onions and the acidity of the vinegar. It is harmless and does not affect the flavor.

Can I use white vinegar instead of apple cider?

Yes, but white vinegar is significantly more aggressive and lacks the subtle sweetness of apple cider vinegar. If you use white, consider adding a touch more sugar.

Community kitchens

How real cooks make it.

No one’s shared their version yet. Be the first to put your kitchen on the map.

Your turn

Cook this your way?

Share your version — your steps, your story. We’ll feature it right here.

Add your recipe