This post may contain affiliate links. Please read my disclosure policy.
This red onion relish is a soft sweet-sour chutney made by caramelizing the onions with sugar and balsamic vinegar, the perfect complement to Burgers, Barbecued Beef, Roast Beef and even matured cheese like Pecorino, Gruyère or Comte.
Jump to:
Why red onions
I like to use red onions for this recipe as they have a soft sweet flavour that nicely balances the balsamic vinegar. This relish gently breaks the strong taste of grilled meat or matured cheese softening their flavours.
You can substitute with regular yellow onions but the flavour will be stronger and slightly more acidic, although still a nice soft sweet and sour topping to add to your meat.
What do you serve with it
When I make these caramelized onions, I always make a large batch. They last at least 3 to 4 days and my sons used them with different types of meat.
I may make it as a topping for roast beef or barbecued beef, and my son will use them the following days to top their hamburgers or even their hotdogs.
You can also serve the red onion relish at room temperature with a cheese platter, it is perfect with strong matured cheese or to top a simple quiche with goat cheese.
How to make onion relish
- Cut the onions into vertical slices, and fry them at medium heat with butter and olive oil
- Once they become translucent lower the heat,
- Add the salt, sugar and balsamic vinegar
- Simmer for 20 minutes, stirring from time to time.
- You can serve it immediately with a warm meal, or at room temperature in a sandwich.
Top tips
- Use a good balsamic vinegar from Modena, not the commercial one
- Simmer the onions at medium heat to make sure they don’t burn
- Turn then regularly
- They will keep for 3 to 4 days
- You can serve them warm or at room temperature but not straight from the fridge
- If you are cooking the onion at very low heat, it may take longer than 20 minutes. Taste them to make sure they are properly cooked and caramelized
More onion recipes
If you like onions, here are some recipes you should definitely try:
If you are making this red onion relish, leave your comment below I would like to hear from you. You can find more delicious ideas if you FOLLOW ME on Facebook, YouTube, Pinterest and Instagram or sign up to my newsletter.
📋Red onion relish
Ingredients
- 3 red onion
- 3 tbsp melted butter
- 1 tbsp Olive oil
- 1 tbsp caster sugar
- 2 tbsp balsamic vinegar Best if from Modena
- 1 tsp salt
Instructions
- Cut the onions into vertical slices, and fry them at medium heat with butter and olive oil
- Once they become translucent lower the heat, add the salt, sugar and balsamic vinegar and simmer for 20 minutes, stirring from time to time.
- You can serve it immediately with a warm meal, or at room temperature in a sandwich.
Video
Notes
- Use a good balsamic vinegar from Modena, not the commercial one
- Simmer the onions at medium heat to make sure they don’t burn
- Turn then regularly
- They will keep for 3 to 4 days
- You can serve them warm or at room temperature but not straight from the fridge
- If you are cooking the onion at very low heat, it may take longer than 20 minutes. Taste them to make sure they are properly cooked and caramelized
Danielle
I absolutely enjoy caramelizing onions. It is such a great side to so many of my favorite meals. Great tip about the serving temperature.
Laura
Thanks, yes the temperature is important
Tonje
I made this for hot dogs, but serving it with roast beef is a great idea! This was so flavourful and tasty, and the step by step pictures made it really easy to see if I was doing it right. Thanks!
Laura
Thank you Tonje, I am glad you like it
Bry
Looks yummy!!
Laura
thanks
Jessica
This is my favorite condiment. I keep some in my fridge at all times. I like it best on sandwiches and in salads. Adds a nice zing!
Laura
nice, yes I would add it to any sandwiches