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How to Make Pickled Red Onions

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A beautiful homemade gift or addition to a cheese board, these pickled red onions are CRAZY fast and easy to make! They’re also the perfect make ahead buffet addition and will keep for at least 6 months in the cupboard unopened.

An open jar of pickled red onions with a fork in. Sat on a rustic white wood backdrop with a sealed and labelled jar of pickled red onions, a pickling lid, a jar of cutlery and a light brown napkin in the background.

I’m always on the lookout for easy homemade gift ideas, are you? Hampers are very popular and adding items that you’ve made makes them even more special!

An open jar of pickled red onions with a fork in. Sat on a rustic white wood backdrop with a sealed and labelled jar of pickled red onions, a pickling lid, a jar of cutlery and a light brown napkin in the background.

Team these punchy pickled red onions up with some sweet chilli jam, pickled beetroot and spiced pickled onions? I don’t think you’ll have trouble working out what everyone wants for Christmas each year anymore!

Worried about how tear jerking this is to make? Don’t worry – I’ve a few secrets on how to cut onion without crying!

A sealed jar of pickled red onions with a label tied to it that says 'with love'. Sat on a rustic white wood backdrop with a light brown napkin, a pickling jar lid and a jar of cutlery in the background.

How long do pickled red onions last?

If pickled properly in a sterilised jar (as shown in this post), pickled red onions should last for at least 6 months when unopened and stored in a cool dark place. Once open, it will keep for around 6 weeks in the fridge.

A birds eye view of an open jar of pickled red onions with a fork in it. Set on a rustic white wood backdrop with a sealed jar of pickled red onions, a light brown napkin, a pickling jar lid and some chopped parsley in the background.

Are pickled red onions good for you?

I wouldn’t say they’re good for you, even though they are technically a vegetable. The vinegar they’re pickled in contains quite a bit of sugar and salt and we all know these aren’t good for you when you eat a lot. All things in moderation!

An open jar of pickled red onions with a fork in. Sat on a rustic white wood backdrop with a sealed and labelled jar of pickled red onions, a pickling lid, a jar of cutlery and a light brown napkin in the background.

What pairs well with pickled red onions?

These beauties make so many things so much better! Here’s a few ideas what you can enjoy them with…

  • On a sandwich
  • As part of a cheese board
  • In burritos
  • On a pizza
  • With pasta
  • In salads
An open jar of pickled red onions with a fork in. Sat on a rustic white wood backdrop with a sealed and labelled jar of pickled red onions, a pickling lid, a jar of cutlery and a light brown napkin in the background.

How long before you can eat pickled onions?

You could eat them straight away but I highly recommend leaving them for about a month. This allows them to soften a little and the flavours to really develop.

A sealed jar of pickled red onions with a label tied to it that says 'with love'. Sat on a rustic white wood backdrop with an open jar of pickled red onions, a light brown napkin, a pickling jar lid and a jar of cutlery in the background.

How do you pickle red onions?

It honestly couldn’t be quicker or easier!

  1. Preheat your oven, place your jar on a baking tray and bake for 20 mins to sterilise it.
  2. Put vinegar, sugar and salt in a pan over a low heat. Stir to dissolve and leave on the heat to stay hot.
  3. Slice the red onions finely and place into a sieve.
  4. Pour boiling water over the red onions then push them into the sterilised jar.
  5. Pour in the hot vinegar and seal.
An open jar of pickled red onions with a fork in. Sat on a rustic white wood backdrop with a sealed and labelled jar of pickled red onions, a pickling lid, a jar of cutlery and a light brown napkin in the background.

Pickled red onions ingredients

Here is everything you need to know about the ingredients needed for this recipe…

  • Vinegar – I recommend using cider vinegar for flavour purposes.
  • Sugar – Any white sugar will work fine, I used granulated.
  • Salt – Table salt will work great here. No need for fancy sea salt etc.
  • Red Onions – The jewel of the recipe, use small, fresh red/purple onions
A birds eye view of an open jar of pickled red onions with a fork in it. Set on a rustic white wood backdrop with a light brown napkin, a pickling jar lid and some chopped parsley in the background.

Recipe tips

We are only human and we all make mistakes! Here’s a few tips that I think will help you get this pickled red onions recipe right first time.

  • Never put hot glass jars on a cold surface as they could crack.
  • If you’re planning on storing this unopened for a while, don’t use clip top jars with rubber seals as they can disintegrate over time.
  • Slice your onions as finely as you can to achieve the best texture.
  • To achieve proper preserving, ensure everything is hot when you seal it. (The jar, the vinegar and the onions.)
  • Feeling adventurous? Add flavour and spices to the vinegar like chilli flakes, peppercorns, capers etc
An open jar of pickled red onions with a fork in. Sat on a rustic white wood backdrop with a sealed and labelled jar of pickled red onions, a pickling lid, a jar of cutlery and a light brown napkin in the background.

Other recipes you might like…

An open jar of pickled red onions with a fork in. Sat on a rustic white wood backdrop with a sealed and labelled jar of pickled red onions, a pickling lid, a jar of cutlery and a light brown napkin in the background.

Pickled Red Onions – Step by Step Picture Recipe

Here is what you will need to make 1 x 500ml jar.

(For a printer friendly version, see the recipe card at the end of this post)

Ingredients

  • 200 – 250ml (3/4 Cup – 1 Cup) Cider Vinegar
  • 3 tbsp Sugar
  • 1 tbsp Salt
  • 2 Small Red Onions

Essential equipment

  • 500ml Pickling Jar
  • Baking Tray
  • Small Saucepan
  • Chopping Board
  • Sharp Knife
  • Kettle or Large Pan
  • Sieve

Instructions

First thing’s first, preheat your oven to 190ºC/Fan 180ºC/374ºF and place your jar (minus the lid) on a baking tray. Bake for 20 mins to sterilise.

a glass jar on a black baking tray ready for sterilising in the oven

Next, measure out the vinegar (200 – 250ml | 3/4 Cup – 1 Cup), sugar (3 tbsp) and salt (1 tbsp) into a small saucepan and set over a low heat.

Cider vinegar, sugar and salt in a small saucepan over a low heat on the stove

Stir until the sugar and salt have dissolved then reduce the heat to keep the vinegar hot until we need it later.

Sugar and salt dissolved in cider vinegar in a small saucepan set over a low heat on the stove

Meanwhile, peel and halve the red onions (2 x small) on a chopping board. Then, using a sharp knife, slice them as finely as you can. Not a fan of your eyes stinging/watering when you cut onions? Here’s how to cut onion without crying.

chopped red onions on a green chopping board with a sharp knife

When your jar is almost ready, fill a kettle full of water and boil. (Alternatively, fill a large pan with water and bring it to the boil.) Place the finely sliced onion into a sieve set over a sink and pour the boiling water over it.

Boiling water being poured over sliced red onions in a sieve set over a sink

Take the jar out of the oven, place onto a surface that is NOT cold and push the hot onion straight into it. Be careful not to burn yourself – I like to wear rubber gloves to help with this.

Hot sliced red onions being stuffed into a hot sterilised glass jar

Finally, pour the hot vinegar into the jar, making sure it covers all the onions, and screw/ the lid as tightly as you can.

Hot pickling vinegar being poured into a jar of sliced red onions

Allow to cool completely on a worktop at room temperature. As it cools, everything will contract (after being expanded due to the heat) and seal.

A sealed glass jar of pickled red onions

How to store pickled red onions

Once cooled, store in a cool dark place for up to 6 months. When opened, keep refrigerated and consume within 6 weeks.

A birds eye view of an open jar of pickled red onions with a fork in it. Set on a rustic white wood backdrop with a sealed jar of pickled red onions, a light brown napkin, a pickling jar lid and some chopped parsley in the background.

Have you made this recipe?

Have you made this insanely indulgent no bake Baileys cheesecake? I’d love to know if you have! Send me your pics, comments and questions on Facebook, Twitter and Instagram or email me at emma@kitchenmason.com.

A sealed jar of pickled red onions with a label tied to it that says 'with love'. Sat on a rustic white wood backdrop with a light brown napkin, a pickling jar lid and a jar of cutlery in the background.

Loved this recipe? Pin it!

An open jar of pickled red onions with a fork in. Sat on a rustic white wood backdrop with a sealed and labelled jar of pickled red onions, a pickling lid, a jar of cutlery and a light brown napkin in the background.
An open jar of pickled red onions with a fork in. Sat on a rustic white wood backdrop with a sealed and labelled jar of pickled red onions, a pickling lid, a jar of cutlery and a light brown napkin in the background.

Easy Pickled Red Onions - Printable Recipe

Yield: 1 x 500ml Jar
Prep Time: 20 minutes
Total Time: 20 minutes

A lovely homemade gift or cheese board addition, these punchy pickled red onions are super fast and easy to make!

Ingredients

  • 200 – 250ml (3/4 Cup – 1 Cup) Cider Vinegar
  • 3 tbsp Sugar
  • 1 tbsp Salt
  • 2 Small Red Onions

Essential Equipment

  • 500ml Pickling Jar
  • Baking Tray
  • Small Saucepan
  • Chopping Board
  • Sharp Knife
  • Kettle or Large Pan
  • Sieve

Instructions

  1. Preheat the oven to 190ºC/Fan 180ºC/374ºF. Place your jar (not the lid) on a baking tray and bake for 20 minutes to sterilise.
  2. Add the vinegar, sugar and salt into a small saucepan and set over a low heat.
  3. Stir until everything is dissolved then leave over a very low heat to keep it hot.
  4. Peel and halve the red onions on a chopping board. Slice the onion as finely as you can using a sharp knife.
  5. Once your jar is almost ready, fill a kettle and boil. (Or fill a large pan with water and bring to the boil over a high heat.) Place the sliced onions into a sieve over a sink and pour the boiling water over them.
  6. Remove your jar from the oven, place on a non cold surface, and immediately push the onions inside.
  7. Pour the hot vinegar in, ensuring you completely cover the onions.
  8. Seal the lid tightly and allow to cool completely at room temperature.

Notes

Store unopened in a cool/dark place for up to 6 months.

Once opened, keep refrigerated and use within 6 weeks.

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Nutrition Information:
Yield: 20 Serving Size: 1
Amount Per Serving: Calories: 41Total Fat: 0gSaturated Fat: 0gTrans Fat: 0gUnsaturated Fat: 0gCholesterol: 0mgSodium: 356mgCarbohydrates: 4gFiber: 0gSugar: 3gProtein: 0g

Nutritional information on kitchenmason.com should only be used as a general guideline, I am not a certified nutritionist. Please always check labels for allergens where applicable.

Did you make this recipe?

I'd love to hear about it! Please leave a comment on the blog or tag me on Instagram.

About Emma Mason

Emma is a professional blogger. Utilising over 20 years of cooking experience, she’s passionate about making your life easier, one recipe at a time! Drawing on her 12+ year background in recipe research and development, photography, copy writing and marketing, Emma has turned kitchenmason.com into a successful career. Known as ‘the organisation queen’ among friends, she is passionate about creating easy to follow recipes that anyone can follow and enjoy. She lives in Nottingham (UK) with her husband, daughter and 2 naughty cats. In her spare time she can be found reading a good book, training at the dojo preparing for her black belt grading, or dreaming up the next crazy colour combo for her hair!

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