Marmite Caramelised Onions
These marmite caramelised onions are sweet, sticky & have a deep, unami flavour. They’re super easy to make & go great in burgers, sandwiches & loads more!
We’re giving caramelised onions a big flavour boost by adding in a spoonful of marmite! These sticky marmite onions have a deep, savoury, unami flavour thanks to the added yeast extract. They’re sweet, salty, sticky & delicious! They go great in burgers, cheese toasties, quiches, omelettes & loads more…
Even if you’re not a marmite fan, you’re sure to love these caramelised onions! Think of the marmite as more of a seasoning than anything else. It helps cut through the sweetness from the caramelised onions, which balances out the flavours. Don’t worry, the onions don’t just taste like marmite!
For more sides & sauces, check out our ever growing collection of side dish recipes!
What You’ll Need
- Onions – I like to use brown onions when making caramelised onions as they have a higher natural sugar content. White onions, red onions & shallots will all work as well though.
- Marmite – Marmite is a thich, spreadable yeast extract with a salty, savoury, unami flavour. This is available from most supermarkets.
- Butter – As marmite is quite salty, it’s best to use unsalted butter to cook the onions in.
- Sugar – We’re adding a small amount of dark brown sugar to the caramelised onions, to make them extra sticky & caramelised!
- Vinegar – Adding a splash of balsamic vinegar to our caramelised onions helps cut through all of that sweetness!
- Chopped Thyme – Fresh thyme adds extra flavour.
How To Make Marmite 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! Make sure to separate the onion slices as well, 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 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!
You’ll need to start stirring the onions more regularly as they begin to caramelise, so that they don’t catch on the bottom of the pan. - Add Vinegar & Sugar
Once the onions are caramelised, we stir in marmite, a small amount of brown sugar, balsamic vinegar & some chopped thyme. - Cook Until Sticky
Now we continue cooking the onions for another 5-10 minutes, until they are sticky & jammy then we season them with black pepper & they’re good to go!
Tips & Tricks
- Use brown onions as they have a high amount of natural sugar, so will caramelise perfectly.
- Don’t slice your onions too thin as they’ll turn to mush! However, they also shouldn’t be too thick. Aim for a thickness of around 2-3mm.
- Cook your onions in butter over a low heat until they turn a deep golden brown. This will take at least 45 minutes, so there’s no need to rush!
- Add a small amount of sugar into the onions at the very end, to make them extra sticky & caramelised.
- Marmite is fairly salty, so your caramelised onions won’t need any extra salt. Adding in some freshly cracked black pepper works fantastically though.
Serving Suggestions
Caramelised marmite onions have a richer, more savoury, unami flavour (like soy sauce) than regular ones but can be used exactly the same. They’re good in sandwiches & burgers, with steaks, in tarts and in pasta sauce. They’re especially good in cheese toasties & sausage rolls!
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.
Caramelised onions will take at least 45 minutes to cook over a low heat, depending on how many onions your are cooking. The key to properly caramelising onions is to cook them for a long time, over a low heat.
Onions are caramelised properly when they turn a deep golden brown. You won’t need to add any extra sugar into your onions as they contain enough natural sugar to caramelise without it.
Caramelised marmite onions should be stored in the fridge & will keep for up to 4 days.
The best marmite substitute would be vegemite, however other similar yeast extracts would work as well.
To cook caramelised onions on an Aga, use the simmering plate.
More Sides & Sauces To Try!
- Chip Shop Curry Sauce
- Béarnaise Mayo
- Rice Krispie Fried Mozzarella Sticks With Hot Honey
- Courgette Tzatziki
- Candied Jalapeños (Cowboy Candy)
- Sweet Pickled Red Cabbage
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Marmite Caramelised Onions
Equipment
- Large Saucepan
Ingredients
- 6 Brown Onions
- 1 tbsp Vegetable Oil
- 60 g Unsalted Butter
- 40 g Marmite
- 30 g Dark Brown Sugar
- 2 tsp Balsamic Vinegar
- 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 & sliced onions into a large saucepan then set over a low heat.
- Cook the onions, stirring regularly until they turn a deep, golden brown. This will take at least 45 minutes.You'll need to stir the onions more regularly as they start to caramelise, to stop them catching on the bottom of the pan.
- Once your onions are caramelised, stir in the marmite, brown sugar, chopped thyme & balsamic vinegar then keep cooking for another 5-10 minutes until the onions are sticky & jammy.
- Once cooked, take the pan off the heat then season the onions with freshly cracked black pepper.
- Serve the onions straight away or alternatively, let them cool down then store in the fridge (they're best served at room temperature!).
