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Onion relish is a simple yet flavorful condiment that’s perfect for topping burgers, hot dogs, and sandwiches. This tested canning recipe brings out the natural sweetness of onions with a tangy vinegar brine.
Onion relish might not get as much attention as its cucumber-based cousins, but it deserves a place on your pantry shelf. With just a handful of ingredients, this easy preserve turns ordinary onions into a bright, tangy topping you’ll want to use on everything. It’s especially good on grilled meats and sausages, but it also adds depth to potato salads, sandwiches, and even cheese boards.
This recipe comes from So Easy to Preserve by the University of Georgia Extension, a trusted source for safe canning guidelines. It’s incredibly flexible, and you can slice the onions thin for a more traditional relish texture, or dice them finely if you’d prefer a spoonable condiment that blends more easily into recipes. A quick blanch keeps the onions from overpowering the brine and helps them hold their shape during storage.
The brine is a classic mix of vinegar, sugar, and salt, with optional mustard seeds for flavor and color. You can easily tweak the spices to suit your taste—celery seed is a natural fit here if you want a touch of old-fashioned relish flavor. Either way, the result is a crisp, tangy condiment that keeps beautifully in a water bath-sealed jar.
If you’ve never made onion relish before, this is a great place to start. It’s quick, budget-friendly, and endlessly useful in the kitchen. Once you’ve tasted how much flavor you can coax out of a few humble onions, you might find yourself putting up a batch every season.
Ingredients for Onion Relish
This recipe is all about letting the onions shine. You only need a few pantry staples, and the flavor is surprisingly bold for such a simple mix.
- Onions – The star of the show. Choose yellow onions for a classic sweet-tangy flavor, or use red onions for a hint of color and a slightly milder taste. You can slice them thin or dice them fine depending on how you want to use the finished relish.
- Vinegar – White vinegar with 5% acidity ensures safe preservation while giving the relish a bright, tangy finish. You can use apple cider vinegar if you prefer a mellower flavor, but always stick to 5% acidity.
- Sugar – Balances the acidity and helps bring out the natural sweetness in the onions.
- Canning Salt – Enhances flavor without the additives found in table salt.
- Mustard Seeds (optional) – These add subtle spice and a pop of texture. You can swap them out for celery seed or omit them altogether if you prefer a cleaner flavor.
How to Make Onion Relish
Start by peeling your onions and deciding how you want them cut. Thin slices work great for topping sausages, while a ¼-inch dice is more versatile and easier to stir into salads or spreads. Once prepped, blanch the onions in boiling water for 4–5 minutes to soften them slightly and take the edge off their sharpness.
While the onions are draining, prepare your canning setup: heat your jars, set your lids in warm water, and bring a water bath canner to a simmer. In a large saucepan, combine vinegar, sugar, salt, and mustard seeds (if using), and bring the mixture to a boil. Add the drained onions to the brine and simmer for 5 minutes, stirring to coat everything evenly.
Using a slotted spoon, pack the onions into hot jars, leaving ½ inch headspace. Ladle brine over the onions to cover, maintaining the same headspace. Debubble the jars, adjust headspace if needed, and wipe the rims before applying the two-part lids fingertip-tight.
Process the jars in a boiling water bath canner for 10 minutes (adjusting for your elevation as needed), then turn off the heat and let them rest for 5 minutes before removing to cool on a towel-lined counter.
Altitude Adjustments
To ensure food safety, increase your processing time depending on elevation:
- 0 to 1,000 feet – 10 minutes
- 1,001 to 6,000 feet – 15 minutes
- Above 6,000 feet – 20 minutes
Serving Onion Relish
This onion relish is bright, tangy, and slightly sweet—perfect for adding a pop of flavor to everything from grilled brats to roasted vegetables. It’s particularly tasty on hot dogs and burgers, where it adds both texture and acidity. Try stirring a spoonful into egg salad, potato salad, or even tuna salad for extra zing.
You can also use it as a cheese board accompaniment, pairing beautifully with sharp cheddar or soft goat cheese. Because the flavor is so balanced, a little goes a long way—but it’s likely you’ll find yourself reaching for it more often than expected.
Onion Relish
Equipment
Ingredients
- 8 cups onions, thin sliced or diced (about 2½ lbs whole onions)
- 1½ cups white vinegar, 5% acidity, or another vinegar such as apple cider at 5% acidity
- 1 cup sugar
- 1 tsp canning salt
- ½ tsp mustard seeds, optional
Instructions
- Peel onions and cut them in half. Slice thinly or dice into ¼-inch pieces, depending on your preference.
- Bring a large pot of water to a boil. Add the onions and blanch for 4–5 minutes. Drain and set aside.
- Prepare a water bath canner, jars, lids, and rings.
- In a saucepan, combine vinegar, sugar, salt, and mustard seeds (if using). Bring to a boil.
- Add the blanched onions and simmer for 5 minutes, stirring occasionally.
- Use a slotted spoon to fill jars with onions, leaving ½-inch headspace. Ladle hot brine over the onions, maintaining headspace.
- Debubble jars, wipe rims, and apply two-part canning lids.
- Process in a boiling water bath canner for 10 minutes (adjusting for altitude).
- Let jars rest in the canner 5 minutes before removing. Cool for 12–24 hours and check seals before storing.
Notes
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Easy Relish Recipes
If you enjoy canning relish, there are lots of styles to try. Sweet Pickle Relish is a crowd-pleaser, especially on hot dogs or in deviled eggs. For something tangy and classic, go with Dill Relish or Classic Pickle Relish. Cucumber Relish has a clean flavor with subtle spices, while Zucchini Relish is a clever way to use summer squash.
Don’t miss out on regional favorites like British Piccalilli, Southern Chow Chow, New England Piccalilli, or Amish Chow Chow—each brings its own twist on traditional relish flavor.
