Pickled Red Onions with Apple Cider Vinegar: A Simple Refrigerator Recipe

A forkful of pickled red onions adds tang and crunch to a black bean taco, avocado toast, or a bowl of roasted vegetables. Apple cider vinegar gives the brine a fruity edge, and the pink onions bring color to the plate.

This recipe uses a simple sour brine and three steps: slice, make the brine, and refrigerate. Plan ahead: the onions need 1–2 days in the fridge for the flavor to develop. They are refrigerator pickles, not a recipe for shelf-stable canning.

Ingredients

• Red onions, enough to fill your jars snugly; start with about 2 medium onions
• 1 cup food-grade apple cider vinegar, such as Fairchild’s; check for at least 5% acidity
• 1 cup water
• 1 tablespoon canning or pickling salt
• 2 teaspoons granulated sugar
• Optional: a few whole peppercorns or a pinch of chili flakes

The brine makes about 2 cups before boiling. The number of jars you fill depends on the size and quantity of your onions. Have clean, heatproof pint jars and lids ready, plus a small stainless steel saucepan.

The brine quantities and cooking method follow Oklahoma State University Extension’s refrigerator onion recipe. Use the measured proportions rather than topping jars up with plain water.

1. Slice and pack

Peel and rinse the onions. Cut them in half, then slice thinly into half-moons. Pack the slices snugly into washed, heatproof jars, allowing room for the brine and headspace. Add the optional spices here if using.

Thin slices are easy to tuck into sandwiches and scatter over tacos. Keep the slices reasonably even so the finished texture is consistent.

2. Make the brine

Combine the vinegar, water, pickling salt, and sugar in the saucepan. Stir, bring to a boil, and boil for 2 minutes. Remove from the heat.

Choose a commercial food vinegar with a stated acidity. Avoid homemade vinegar or products of unknown strength. Do not reduce the vinegar or increase the water in this recipe; Oregon State University Extension explains why vinegar strength and proportions matter when pickling.

3. Chill and enjoy

Carefully pour the hot brine over the onions, covering them while leaving ½ inch below each jar’s rim. Add the lids and refrigerate. Mark the jars with the preparation date.

Let the flavor develop for 1–2 days. Keep refrigerated and use within 2 weeks, following University of Maine Cooperative Extension’s refrigerator pickle guidance. If you need more brine, make another batch using the same proportions.

What to put them on

• Black bean tacos with avocado and cilantro
• Hummus wraps with cucumber and greens
• Roasted sweet potato and quinoa bowls
• Avocado toast or a grilled cheese sandwich

Lift out a small portion and let the excess brine drain before serving. Start with a little; these onions are a tangy accent.

Can these go in the pantry?

No. Keep these prepared onions in the refrigerator. The storage advice for a bottle of plain vinegar does not carry over to vegetables mixed with vinegar and water. For pantry storage, use a separate, tested canning recipe and its complete processing instructions.

The bottle in this recipe

We feature Fairchild’s Organic Apple Cider Vinegar, which we sell at AppleCiderVinegar.com. Check the acidity on your bottle before measuring. The vinegar supplies the tang; the recipe works through its brine proportions and refrigeration.

For another everyday use, try our apple cider vinegar salad dressing.