Caramelized Onions

These homemade caramelized onions are sweet, sticky, soft and delicious. Better still, they couldn’t be easier to make!

Let me tell you this straight off the bat – caramelized onions are a labour of love. In my humble opinion there is no such thing as ‘quick caramelized onions’. Caramelized onions are incredibly easy to make but they do take a little time. 100% worth it though. Follow me…

The Humble Onion

It’s hard to believe that onions can turn so sweet after you’ve just spent a good 10mins crying from the acidity of chopping them 😂  Onions are packed with natural sugars and it’s our duty as cooks to draw out that sugar and bring it to the surface of the onions to caramelize. Because realistically is there anything better in this world than caramelized onions? No, the answer is always no.

What Onion to use?

Most variety of onion works great (white, sweet, red or yellow) and you can either finely diced the onion or slice into thin strips. In all cases I recommend finding the largest onions you can find, just so you don’t have to fart about with slicing 2lb/1kg worth of small onions.

Oil or Butter?

I actually use a 50/50 split of both. The butter adds a gorgeous rich flavour to the butter whilst the oil helps protect them from browning/sticking to the pan.

To begin the caramelization process you’ll initially want to get as much moisture out of the onions as possible without letting them char. This is important, you don’t want them to catch on the pan at any point, so don’t start off any higher than a medium heat.

Once the onions start to soften, you’ll notice them start to steam less. At this point you’ll want to turn down the heat slightly and season with salt and pepper. Don’t brush over the seasoning, these are crucial ingredients. The salt helps balance out the sweetness of the onions, so does the slight spice from the black pepper.

At this point the onions will naturally start to caramelize. Remember I mentioned the natural sugars creeping out of the onions as they fry? Yup, you’ll notice they start to go nice and soft/golden. Now is the time to introduce your two new best friends:

1. Balsamic Vinegar

Adding balsamic vinegar serves a few different purposes:

• Deglazes the pan.
• Deepens the colour of the onions.
• Balances out the sweetness with a touch of acidity.

Don’t sub any other vinegars, balsamic is by far the most suited for caramelizing onions.

2. Brown Sugar

Whilst you can get ultra sweet caramelized onions without sugar, it does help along with the process. Caster sugar is too sweet, so stick with brown.

From there, you’ll want to turn down the heat to a low and gently fry until the onions turn soft & sticky and turn to a deep golden colour.

How long does it take to caramelize onions?

The aim of the game with caramelized onions is low and slow. I’ve spent the best part of 2 hours caramelizing onions on low heat before and they were incredible. But in general you’re looking at a minimum of an hour.

How to store caramelized onions?

Allow to cool then tightly cover in the fridge for 3-4days (longer at your discretion) or in the freezer for up to 3 months!

Serving Caramelized Onions

These are perfect in burgers, great as part of a cheese board, served with Hummus and of course perfect in sandwiches! Sandwiches that I add Caramelized Onions to include: Brie Grilled Cheese, Portobello Mushroom Sandwich and Corned Beef Sandwich.

If you like the sound of this recipe I have a sneaky suspicion you’ll love my Homemade Tomato Chutney!

Alrighty, let’s tuck into the full recipe for these caramelized onions shall we?!

How to Caramelize Onions (Full Recipe & Video)

Homemade Caramelized Onions

These homemade caramelized onions are sweet, sticky, soft and delicious. Better still, they couldn't be easier to make!

5 from 9 votes

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Course: Condiment

Cuisine: Universal

Prep Time: 10 minutes minutes

Cook Time: 1 hour hour

Total Time: 1 hour hour 10 minutes minutes

Servings (click & slide): 8

Calories per serving: 70kcal

Author: Chris

Cost per serving: £1 / $1

Equipment

• Large Non-Stick Pan
• Sharp Knife & Chopping Board
• Wooden Spoon

Ingredients

• 2lb / 1kg Onions, peeled & sliced (white, sweet, red or yellow onions all work great)
• 2 tbsp Brown Sugar
• 2 tbsp Balsamic Vinegar
• 1 tbsp Olive Oil
• 1 tbsp Butter (or a 2nd tbsp olive oil)
• 3/4 tsp Salt
• 1/4 tsp Ground Black Pepper

Instructions

• In a large non-stick pan over medium heat add 1 tbsp butter and 1 tbsp olive oil. Give it a stir and when the butter melts add in your onions. Fry for 15-20mins, or until they start to soften. If they start browning/charring at any point turn down the heat, this step is merely to soften the onions and try and get out some moisture. Season with salt and pepper.
• Turn heat down to low-medium and continue frying for another 20mins or until the onions start turning golden. Again, don't let them catch and start crisping/charring. Add in 2 tbsp balsamic vinegar and 2 tbsp brown sugar.
• Turn heat to low and continue gently frying until the onions turn a deeper golden colour and start to become sticky. The onions should be soft and gooey.

Quick Demo

Notes

a) Onion Size - I recommend using the biggest onions you can find (4 pomegranate sized onions are approx 2lb/1kg). This will reduce chopping time and in turn, the amount of time you spend crying over a chopping board of onions!

b) Low 'n' Slow - The aim of the game with caramelizing onions is to fry them low and slow. This is to tickle out the natural sugars in the onions and bring them to the surface so they caramelize. Timings will depend on the size & depth of your pan, as a lot of the initial cooking is steaming the onions to get out all the moisture. I have spent the best part of 2 hours caramelizing onions on a low heat before and they were incredible! Remember, low and slow. Don't rush this.

c) Storage - Allow the onions to completely cool then store in the fridge for 3-4days. You can also freeze them for up to 3 months! Just thaw in the fridge and use as necessary.

d) Calories - based on 1 serving (1/8th of recipe):

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Nutrition:

Nutrition Facts

Homemade Caramelized Onions

Amount Per Serving

Calories 70 Calories from Fat 25

% Daily Value*

Fat 2.81g4%

Saturated Fat 0.855g5%

Trans Fat 0.001g

Polyunsaturated Fat 0.219g

Monounsaturated Fat 1.547g

Cholesterol 2mg1%

Sodium 242mg11%

Potassium 147mg4%

Carbohydrates 10.68g4%

Fiber 1.1g5%

Sugar 7.58g8%

Protein 1.02g2%

Vitamin A 32IU1%

Vitamin C 5.6mg7%

Calcium 27mg3%

Iron 0.38mg2%

* Percent Daily Values are based on a 2000 calorie diet.

*Nutrition is based on the absence of salt unless stated as a measurement in the ingredients. Cost is worked out based on ingredients bought from UK supermarkets, then divided by the number of servings. In both instances these values are just for guidance. Please check out my FAQ Page for more info.

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