Quick Pickled Red Onions

If the FryDaily fridge holds one small jar that improves everything it touches, it is this one. Red onions, sliced thin and covered with a warm vinegar brine, turn a vivid pink and lose their raw bite within half an hour, keeping a gentle crunch and a sweet-tart snap. Tacos, grain bowls, salads, sandwiches, burgers, eggs — a forkful of these onions is the difference between a good plate and a plate people ask about.

One honest label, as with our Refrigerator Dill Pickle Spears: this is a refrigerator pickle. It is not processed, it is not shelf-stable, and it lives in the fridge for its whole life. For pantry pickles you need a tested water-bath recipe followed exactly, like the ones in our Canning and Preserving collection. What the fridge method gives you in return is speed and crunch no processed jar can match.

The brine is deliberately simple — vinegar, water, a little sugar and salt — because the onions are the flavor. Once the base jar is in your fridge, variations suggest themselves: a sliced jalapeno for heat, a bay leaf and peppercorns for depth, a strip of orange peel when the onions are headed for rich, fatty meats.

Slice thin, slice even

Thickness decides both speed and texture. Half-moons sliced about 1/8 inch (3 mm) thick soften into the brine in thirty minutes and drape nicely over food; thick slices stay harsh in the middle for hours. A mandoline makes fast, even work of it — use the guard, always — but a sharp knife and a steady hand do fine. Slice from pole to pole rather than across the equator: the strips hold together better in the jar and look prettier on the plate.

Warm brine, not boiling

The brine should be hot enough to dissolve the salt and sugar and take the raw edge off the onions, but a hard boil poured over thin slices cooks them limp. Heat the mixture just until it steams and the solids dissolve, let it stand for a minute, then pour. The onions will slump into the jar and turn pink from the edges inward — the color change is the vinegar reacting with the onion's natural pigments, and a pale batch usually just needs another hour in the fridge.

Ingredients

• 2 medium red onions, about 1 lb total (450 g)
• 3/4 cup apple cider vinegar (180 ml)
• 3/4 cup water (180 ml)
• 1 1/2 tablespoons granulated sugar (18 g)
• 1 1/2 teaspoons fine salt (9 g)
• 1 teaspoon black peppercorns (3 g), optional
• 1 bay leaf, optional
• 1 small jalapeno, thinly sliced (about 15 g), optional, for heat
• 1 garlic clove, smashed (about 3 g), optional

Amounts are for the yield below. US customary measures first, grams in brackets for scale users.

Step-by-step instructions

1. Slice the onions. Peel the onions, trim the ends, and halve them from pole to pole. Slice each half into thin half-moons about 1/8 inch (3 mm) thick, keeping the slices as even as you can. Separate the layers gently with your fingers as you work.
2. Pack the jar. Pack the onion slices into a clean 1-pint (475 ml) jar or a heatproof container, tucking the peppercorns, bay leaf, jalapeno and garlic, if using, down among the slices as you go. Pack them in fairly snugly — they will slump as the brine softens them — but do not crush them.
3. Make the warm brine. Combine the vinegar, water, sugar and salt in a small saucepan. Heat over medium heat, stirring, just until the mixture steams and the sugar and salt have fully dissolved, 2 to 3 minutes. Take it off the heat and let it stand for 1 minute — warm, not boiling, is the goal.
4. Pour and press down. Pour the warm brine slowly over the onions, nudging them with a clean spoon as you go so the liquid reaches every layer and the slices are fully submerged. If a few slices float above the surface, press them down; they will settle as they soften.
5. Rest until pink. Let the jar cool at room temperature for about 30 minutes, by which time the onions will have turned a vivid pink and softened into the brine. They are ready to eat at this point, and better still after a few hours in the refrigerator.
6. Refrigerate and use. Seal the jar and refrigerate. Use clean utensils to lift onions from the jar so the brine stays fresh, and enjoy them on everything for the next few weeks — the flavor mellows and deepens as the days pass.

Nutrition estimate

Nutrition figures are estimates calculated from standard ingredient data for the yield stated. Your actual values will vary with brands, substitutions and portion sizes — treat them as a guide, not a guarantee.

Storage & reheating

Store the sealed jar in the refrigerator at all times and use within 3 weeks for best flavor and crunch; the onions gradually soften and the pink fades toward the end of that window. Never store these onions at room temperature and never attempt to seal them for the pantry — this recipe is a refrigerator pickle and has not been tested for water-bath canning. If the brine turns cloudy with sliminess or develops an off smell, discard the jar without tasting. Nutrition figures are estimates from standard ingredient data and vary with brands and substitutions, calculated per 1/4 cup (about 30 g) of drained onions.

Quick Pickled Red Onions

★★★★★★★★★★ FryDaily kitchen score 4.8/5 — our own editorial rating from testing, not reader reviews.

Bright pink, tangy and ready in 30 minutes — the little jar that improves everything it touches.

Yield: 8 servings  ·  Scale: 1x2x3x

Prep10 minutes

Cook5 minutes

Total30 minutes

Servings8 servings

Calories20 kcal

Ingredients

• 2 medium red onions, about 1 lb total (450 g)
• 3/4 cup apple cider vinegar (180 ml)
• 3/4 cup water (180 ml)
• 1 1/2 tablespoons granulated sugar (18 g)
• 1 1/2 teaspoons fine salt (9 g)
• 1 teaspoon black peppercorns (3 g), optional
• 1 bay leaf, optional
• 1 small jalapeno, thinly sliced (about 15 g), optional, for heat
• 1 garlic clove, smashed (about 3 g), optional

Tick ingredients off as you prep, and tap a step below to mark it done as you cook. Scaling adjusts the listed amounts - seasoning to taste stays your call.

Instructions

1. Slice the onions. Peel the onions, trim the ends, and halve them from pole to pole. Slice each half into thin half-moons about 1/8 inch (3 mm) thick, keeping the slices as even as you can. Separate the layers gently with your fingers as you work.
2. Pack the jar. Pack the onion slices into a clean 1-pint (475 ml) jar or a heatproof container, tucking the peppercorns, bay leaf, jalapeno and garlic, if using, down among the slices as you go. Pack them in fairly snugly — they will slump as the brine softens them — but do not crush them.
3. Make the warm brine. Combine the vinegar, water, sugar and salt in a small saucepan. Heat over medium heat, stirring, just until the mixture steams and the sugar and salt have fully dissolved, 2 to 3 minutes. Take it off the heat and let it stand for 1 minute — warm, not boiling, is the goal.
4. Pour and press down. Pour the warm brine slowly over the onions, nudging them with a clean spoon as you go so the liquid reaches every layer and the slices are fully submerged. If a few slices float above the surface, press them down; they will settle as they soften.
5. Rest until pink. Let the jar cool at room temperature for about 30 minutes, by which time the onions will have turned a vivid pink and softened into the brine. They are ready to eat at this point, and better still after a few hours in the refrigerator.
6. Refrigerate and use. Seal the jar and refrigerate. Use clean utensils to lift onions from the jar so the brine stays fresh, and enjoy them on everything for the next few weeks — the flavor mellows and deepens as the days pass.

Calories: 20 kcalProtein: 0 gCarbohydrates: 5 gFat: 0 gSaturated fat: 0 gSodium: 440 mgFiber: 1 gSugar: 3 g

Tested in the FryDaily kitchen, October 2026. Printing? This card is designed to print cleanly on its own.

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