Caramelised Onions
Our homemade, caramelised onions are sweet, sticky & jammy. These are cooked low & slow and work great with steaks, burgers, sandwiches, salads & lots more.
If you’ve ever wanted to make your own caramelised onion, we’re going to show you how!
The key to making really good caramelised onions is to slow cook them in butter over a real gentle heat. And the great thing is that, other than a bit of patience, you’ll only need 6 ingredients to make these sweet, sticky, jammy onions!
These onions make a great steak & burger garnish but would also make a fantastic addition to a cheese board, pasta sauces, a homemade quiche, sausage rolls & a whole lot more. They’re great with almost everything & super easy to make!
For more sides & sauces, check out our ever growing collection of side dish recipes!
What You’ll Need
- Onions – We’re using brown onions as they have the highest natural sugar content. Although white onions, red onions or shallots will work as well.
- Butter – Cooking the onions in butter makes them even richer & flavourful. We’re adding a splash of veg oil in with the butter, to stop it burning.
- Balsamic Vinegar – We’re adding a couple of teaspoons of vinegar, to deglaze our onions. The acidity from the vinegar also cuts through the sweetness from the onions, balancing out the flavour.
- Brown Sugar – We’re adding a small amount of brown sugar to our onions once they’re caramelised, to make them extra sticky & jammy.
- Thyme – Used to add extra flavour to our onions. This is optional though or you could use a different herb like rosemary instead.
How To Make Caramelised Onions
The full, printable recipe card for these caramelised onions can be found at the bottom of this post! Here’s a quick rundown of the recipe…
- Slice Onions
First, we need to peel the onions then slice them up. They should be fairly thin. Make sure to use a sharp knife here! Oh & separate the onion slices, so that they cook evenly. - Slow Cook
Next, we add butter & oil into a large pan, melt over a low heat then add in the sliced onions & a big pinch of sea salt. We cook the onions low & slow, stirring regularly until they turn a deep, golden brown. This will take at least 45 minutes! - Add Vinegar & Sugar
Once the onions are caramelised, we deglaze the pan with balsamic vinegar then stir in a small amount of brown sugar & some chopped thyme. - Cook Until Sticky
Now we continue cooking the onions for another 10-15 minutes, until they are sticky & jammy then they’re good to go!
Caramelised Onions Tips & Tricks
- Slice the onions fairly thinly (not too thin though, we want to retain some texture!) then separate the slices.
- Slowly cook the onions in butter & oil until they turn golden brown. This will take at least 45 minutes. Don’t rush this step!
- Deglaze the pan with balsamic vinegar. This adds acidity, which cuts through the sweetness from the onions.
- Add a small amount of sugar in at the very end, to make the onions extra sticky!
Serving Suggestions
Homemade caramelised onions work great with a whole load of things! Popular uses for caramelised onions include steak garnishes & burger toppings but they’d also work in sandwiches, quiches & tarts, on pizzas & hotdogs, in pasta sauces & loads more. I used mine in a homemade steak sandwich!
Frequently Asked Questions
Brown onions are best for caramelising because of their high levels of natural sugars. Although red onions, white onions & shallots will all work as well.
The key to making properly caramelised onions is to cook them over a low heat for a long time. Caramelised onions will take around an hour to cook from start to finish.
Adding vinegar to caramelised onions cuts through & balances out the sweetness from the onions. We’re also using the vinegar to deglaze the pan once the onions are caramelised.
Once cooked, caramelised onions should be stored in the fridge & are best eaten within 3-4 days.
More Sides & Sauces To Try!
- Dauphinoise Potatoes
- Rice Krispie Fried Mozzarella Sticks With Hot Honey
- Cheesy Buttermilk Skillet Cornbread
- Duck Fat Oven Chips
- Triple Cooked Chips
- Cherry Cola Whiskey BBQ Sauce
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Caramelised Onions
Equipment
- Large Saucepan
Ingredients
- 6 Brown Onions (See Notes)
- 75 g Butter
- 1 tbsp Vegetable Oil
- 2 tsp Balsamic Vinegar
- 40 g Dark Brown Sugar
- 1 tsp Finely Chopped Thyme
Instructions
- Trim the tops & bottoms off the onions, cut in half then peel the skins off. Use a sharp knife to slice the onions, fairly thinly.You can keep the onions trimmings for making stock with!
- Next, add the butter & veg oil into a large saucepan then set over a low heat. Let the butter melt then add in the sliced onions & a generous pinch of sea salt.
- Cook the onions, stirring regularly until they turn a deep, golden brown. This will take at least 45 minutes.It's best to stir the onions more frequently as they begin to caramelise, to prevent them catching on the bottom of the pan.
- Once your onions are caramelised, deglaze the pan with the vinegar then stir in the brown sugar & thyme. Continue cooking for another 10-15 minutes, until sticky & jammy then remove from the heat.
- Serve the onions straight away or alternatively, let them cool down then store in the fridge (they're best served at room temperature!).
