Name: Easy French Onion Soup (Foolproof Recipe!)
Prep time: 15 min
Cook time: 75 min
Total time: 150 min
Ingredients: 100 g salted butter; 2 tbsp olive oil; 2.5 kg brown onions (unpeeled weight); 2 tsp sugar; 5 g fresh thyme (or 1 tsp dried (optional)); 3 garlic cloves (finely chopped); 400 ml white wine; 1 tbsp Worcestershire Sauce; 2 tbsp plain flour; 2 rich beef stock pots (or beef stock cubes); 2 litres water; 2 tsp salt; chives or thyme (fresh) (optional garnish); French Baguette; Comte / Gruyere / Cheddar Cheese / Mozzarella

It may look intimidating ... but this Easy French Onion Soup will be the most foolproof version you'll ever make! The worst part of the whole thing is chopping 2.5kg of onions. And even then, I'll equip you with 3 easy steps to ensure perfect results every single time - without needing to be meticulous!

A mug of French onion soup is topped with melted cheese, overflowing down the sides. Two slices of bread are beside the mug on a dark plate. The background includes a blurred plant and kitchen items.

I absolutely adore soup. I especially adore the combination of soup, bread and cheese. So this foolproof, Easy French Onion Soup recipe may be my favourite ever!

Jump to:

Essential Steps For The BEST French Onion Soup!
Ingredients for Easy French Onion Soup
Method: How To Cook Easy French Onion Soup
Storage + Re Heating
And finally…
Easy French Onion Soup (Foolproof Recipe!)

Plus I quite literally made this recipe about 30 times before I was happy with the timings, the top tips and the tricks to making this foolproof! So I'm feeling really confident that you're going to love it too.

Check out the end of this post (just above the recipe card) for some more of my Soup Recipes.

Essential Steps For The BEST French Onion Soup!

You don't need to worry too much about slicing your onions particularly thinly if you follow these steps. Because, let's be honest, slicing 2.5kg of onions ain't an easy task!

Use the lid method i.e. make sure to put a lid on your pot for the first 1 hour! It helps to sweat down and soften the onions.
Ensure you do not skip the 5 minute High Heat section (this will develop some extra colour on the onions) before adding the wine.
Simmer the onions for as long as you can / want (once you've added the stock) - this will reduce and intensify the stock and subsequent flavour of the soup!

Ingredients for Easy French Onion Soup

Ingredients on a wooden surface include a bottle of Worcestershire sauce, a stick of Kerrygold butter, peeled garlic cloves, a bowl of onions, a bowl of flour, a bowl of salt, three beef stock cubes, and a measuring cup of broth.

Salted Butter/ Olive Oil: oil isn't essential, but it's good to add a little oil into the mix when cooking with butter, as it reduces the likelihood of it burning.
Brown Onions
Sugar
Garlic
White Wine: this adds a major flavour boost to the soup, so I would encourage you not to omit it. However, if you need to - just leave it out completely. Don't increase the volume of the liquid (stock) to compensate, as we reduce it down significantly and therefore is negligible.
Thyme (optional): if using fresh, just remember to remove the stalks from the soup before serving. Or substitute for dried thyme.
Worcestershire Sauce
Plain Flour (All Purpose): used as a thickening agent, so fine to use a gluten free substitute if necessary
Beef Stock: I really love to use Knorr Rich Beef Stock Pots in this recipe, as it adds a boost of dark brown colouring to the soup. Normal beef stock is absolute fine as it won't affect the flavour - my preference purely adds to the aesthetics.
Water
Salt

Method: How To Cook Easy French Onion Soup

Add salted butter and olive oil into a pan with brown onions (peeled and thinly sliced), sugar and fresh thyme.

A pot filled with sliced onions surrounds a stick of butter on a stovetop. The onions are neatly arranged, and the butter is centered in the pot, ready for cooking. The pot has two stainless steel handles.

A hand with red nail polish holds a measuring spoon of salt over a pot filled with sliced onions on a stove. The pot has metal handles and the stove is black.

Cook on medium/high heat for 30 minutes with lid on the pot (this will help sweat the onions down), checking after 15 minutes or so and giving it a stir.

A pot filled with sliced onions cooking. The onions are translucent and lightly caramelized, indicating they are being sautéed. The stovetop beneath the pot is slightly visible.

After 30 minutes, add garlic cloves (finely chopped) and Worcestershire Sauce then cook for further 30 minutes at medium/high heat (with lid still on).

A pot filled with caramelized onions is topped with minced garlic in the center. The onions are well-cooked and slightly translucent, with some browned edges. The pot is placed on a black stovetop.

If using fresh thyme, remove the stalks at this stage - the leaves should have come off and will flavour the soup. But the stalks need to be removed.

IMPORTANT STEP: Remove the lid from the pot, turn the heat up to high and cook for 5 minutes, whilst stirring consistently, until you achieve satisfactory caramelisation on the onions - this stage will help to darken the colour of the soup (in addition to the stock)

A pot of caramelized onions, cooked to a soft, golden-brown color, filling the bottom of a black saucepan on a stovetop. The onions appear tender and evenly browned.

Close-up of a pot filled with caramelized onions, golden brown in color, with a slightly glossy texture. The onions are spread evenly across the bottom of the pot, showing a uniform consistency.

Pour in white wine and continue to cook on high heat until it’s nearly all absorbed into the onions (5 - 10 minutes). Then add plain flour and stir through - this will provide a slightly thicker consistency to the soup.

A pot filled with caramelized onions topped with a dusting of white flour. The onions appear golden brown and are spread evenly across the bottom of the pot. The flour is scattered mostly in the center.

Add beef stock (stock cubes) and water (boiling) - stir to dissolve the stock pots

A pot filled with golden-brown caramelized onions, featuring two pieces of black licorice positioned near the center. The mixture has a thick, smooth texture and is evenly spread out across the pot.

A black pot filled with light brown broth is shown. The surface of the broth has a few small bubbles and some herbs are visible, indicating a savory soup being prepared.

Leave on medium/high heat for approx. 60 minutes (this will ensure the onions are totally soft and reduce the liquid to create a gorgeously decadent soup). Finally, add salt to season and get ready to serve.

A pot filled with steaming French onion soup, featuring translucent sliced onions in a rich, brown broth. The pot sits on a black stovetop with two handles visible on either side.

Bread and Cheese Topping Method Options

Turn on the grill and select your serving bowl, whilst preparing slices of French Baguette for each bowl to layer on top.

Option 1: Ladle soup into bowl, place bread on top, and sprinkle with grated cheese blend. Place under a grill, watching closely, until cheese is bubbling and you start to see a little colour. Remove and serve.

Option 2: Add Comte / Gruyere / Cheddar Cheese / Mozzarella (grated) onto slices of French Baguette - melt under a grill then place into soup bowl before garnishing with chives or thyme (fresh) to serve.

A ceramic bowl of French onion soup topped with melted cheese, placed on a black plate. Two slices of baguette sit beside the bowl. A golden charger and green foliage are visible in the background.

A close-up of a person lifting a cheesy, gooey French onion soup out of a white bowl with a spoon. The melted cheese stretches from the bowl, showcasing a golden-brown crust. Greenery is blurred in the background.

Storage + Re Heating

The French Onion Soup can be stored in the fridge for 5 days once cooked.

It can also be stored in the freezer for up to 4 months, and reheated straight from frozen. My fridge is always stocked full of different soup options!

A warm pot pie with a golden-brown crust overflowing slightly on the edges, served in a white ceramic pot. It sits on a black and gold plate with two slices of bread. Greenery and a salt and pepper set are in the background.

And finally…

If you do choose to make it, I hope you enjoy it!

Why not try some of my other Soup Recipes like my:

A bowl of golden-yellow soup garnished with crispy fried onions, fresh cilantro leaves, and a sprinkle of black pepper, served on a wooden table. — slow cooker leek and potato soup

A bowl of creamy soup garnished with croutons, a drizzle of cream, olive oil, and scattered herbs on top. The soup is served in a dark-rimmed bowl on a wooden table. — slow cooker leek and potato soup

If you have any other questions, or want to tell me what you think of my recipe, then please leave a comment below!

Easy French Onion Soup (Foolproof Recipe!)

Lauren

There are a few absolute Must Do's to result in this Foolproof recipe for Easy French Onion Soup and I'm about to break it down for you!

5 from 2 votes

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Prep Time 15

Cook Time 1 15

Caramelisation 1

Total Time 2 30

Course Soup

Cuisine French

Servings

Calories 272 kcal

Ingredients

100 g salted butter
2 tablespoon olive oil
2.5 kg brown onions unpeeled weight
2 teaspoon sugar
5 g fresh thyme or 1 teaspoon dried (optional)
3 garlic cloves finely chopped
400 ml white wine
1 tablespoon Worcestershire Sauce
2 tablespoon plain flour
2 rich beef stock pots or beef stock cubes
2 litres water
2 teaspoon salt
chives or thyme (fresh) optional garnish
French Baguette
Comte / Gruyere / Cheddar Cheese / Mozzarella any cheese you fancy - I'll provide an overview of the options in the Notes section below

Instructions

Add 100 g salted butter and 2 tablespoon olive oil into a pan with 2.5 kg brown onions (peeled and thinly sliced), 2 teaspoon sugar and 5 g fresh thyme.
Cook on medium/high heat for 30 minutes with lid on the pot (this will help sweat the onions down), checking after 15 minutes or so and giving it a stir
After 30 minutes, add 3 garlic cloves (finely chopped) and 1 tablespoon Worcestershire Sauce then cook for further 30 minutes at medium/high heat (with lid still on)
If using fresh thyme, remove the stalks at this stage - the leaves should have come off and will flavour the soup. But the stalks need to be removed.
IMPORTANT STEP: Remove the lid from the pot, turn the heat up to high and cook for 5 minutes, whilst stirring consistently, until you achieve satisfactory caramelisation on the onions - this stage will help to darken the colour of the soup (in addition to the stock)
Pour in 400 ml white wine and continue to cook on high heat until it’s nearly all absorbed into the onions (5 - 10 minutes)
Add 2 tablespoon plain flour and stir through - this will provide a slightly thicker consistency to the soup
Add 2 rich beef stock pots (stock cubes) and 2 litres water (boiling) - stir to dissolve the stock pots
Leave on medium/high heat for approx. 60 minutes (this will ensure the onions are totally soft and reduce the liquid to create a gorgeously decadent soup)
Finally, add 2 teaspoon salt to season and get ready to serve
Turn on the grill and select your serving bowl, whilst preparing slices of French Baguette for each bowl to layer on top.
Option 1 for Cheese Topping: Ladle soup into bowl, place bread on top, and sprinkle with finely cheese blend. Place under a grill, watching closely, until cheese is bubbling and you start to see a little colour. Remove and serve.
Option 2 for Cheese Topping: Add Comte / Gruyere / Cheddar Cheese / Mozzarella (grated) onto slices of French Baguette - melt under a grill then place into soup bowl before garnishing with chives or thyme (fresh) to serve.

Notes

Nutrition Facts are for French Onion soup only - they do not include the French baguette and cheese topping.

Cheese Options:

Traditional Options - Comte and Gruyere (Alpine Cheeses)

Non-Traditional Options - Cheddar and/or Mozzarella

I personally like to use a combination of all of the above - I'm a traditional girl at heart so I usually have Comte in my fridge anyway. But if I want a drool-worthy cheese pull then I'm going to want to add some mozzarella into the mix!

Must Do's For The BEST French Onion Soup!

You don't need to worry too much about slicing your onions particularly thinly if you follow these steps. Because, let's be honest, slicing 2.5kg of onions ain't an easy task!

Use the lid method i.e. make sure to put a lid on your pot! It helps to sweat down and soften the onions.
Ensure you do not skip the 5 minute High Heat section (this will develop some extra colour on the onions)
Simmer and cook the onions once you've added the stock for as long as you can / want - this will reduce and intensify the stock and subsequent flavour of the soup!

White Wine Note: this adds a major flavour boost to the soup, so I would encourage you not to omit it. However, if you need to - just leave it out completely. Don't increase the volume of the liquid (stock) to compensate, as we reduce it down significantly and therefore is negligible.

Please refer to my 'How To' section above if you want a detailed photographic step by step guide on how to make Easy French Onion Soup. This can be especially helpful for seeing the different levels of caramelisation on the onions.

Nutrition

Calories: 272kcalCarbohydrates: 33gProtein: 4gFat: 14gSaturated Fat: 7gPolyunsaturated Fat: 1gMonounsaturated Fat: 5gTrans Fat: 0.4gCholesterol: 27mgSodium: 955mgPotassium: 511mgFiber: 5gSugar: 15gVitamin A: 350IUVitamin C: 25mgCalcium: 86mgIron: 1mg

Keyword classic french onion soup, easy french onion soup, french onion soup, simple french onion soup

Tried this recipe?Let us know how it was!

Essential Steps For The BEST French Onion Soup!

Ingredients for Easy French Onion Soup