French Onion Soup

Recipe video above. One of the most epic soups of the world does take time to make but it's so worth it! The deeply caramelised onions make an incredible flavour base for the broth. And that cheesy toast is a must! See recipe notes for SLOW COOKER Caramelised Onions.

Recipe by Nagi | RecipeTin Eats on November 28, 2018

Prep time: PT20M

Cook time: PT90M

Total time: PT110M

Rating

4.86 stars (492 reviews)

Keywords

French Onion Soup

Ingredients

100 g / 3.5oz unsalted butter
1.25 kg / 2.5 lb brown / yellow onions (, peeled, halved, thinly sliced top to bottom (Note 1))
3/4 cup (185ml) dry white wine (, optional (Note 2))
2 tbsp flour (, plain / all purpose)
1.5 litres / 6 cups / 1.5 quarts good quality beef broth./stock OR chicken (, low sodium/salt reduced (Note 3))
2 dried bay leaves ((or 3 fresh) (optional))
3 sprigs fresh thyme ((optional))
Salt and pepper
6 - 8 slices French baguette (or other softish bread (Note 4))
100 g / 3.5 oz gruyere (or mozzarella cheese, or other melting cheese of choice)
Fresh parsley or thyme leaves (, for garnish (optional))

Cuisine

French

Steps

Caramelise Onions (See Notes for SLOW COOKER option)
- Melt butter in a heavy based casserole pot over medium heat. When it starts to foam, add onions and stir to coat in butter.
- 30 min on medium low: Turn heat down to medium low. Cook for 30 minutes stirring every few minutes, until the onions have softened and are semi transparent. 
- Salt, 20 min on medium high: Turn heat up to medium or medium high. Add salt, and cook for a further 20 - 30 minutes, stirring more regularly, until onions are deep golden and sweet.
Make Soup:
- Deglaze: Add wine, then simmer rapidly for 2 minutes until mostly evaporated, stirring to scrape the bottom of the pot.
- Flour: Sprinkle flour over the onion and cook for 1 minute.
- Add broth & herbs: Add broth, thyme and bay leaves. 
- Simmer: Cover, lower heat so it's simmering gently then simmer for 30 minutes. 
- Serve: Season to taste with salt and pepper. Ladle into bowls. Top with 1 or 2 slices of cheesy toast.
Cheese Toast:
- Preheat grill / broiler to high.Toast each side of bread until light golden.
- Top bread with cheese, then grill until melted and some brown spots appear.

Nutitrion

Serving Size: 435 g
Calories: 386 kcal
Carbohydrates: 34.3 g
Protein: 15.6 g
Fat: 21 g
Saturated Fat: 12.2 g
Cholesterol: 54 mg
Sodium: 1128 mg
Sugar: 6.9 g
Unsaturated Fat: 8.8 g

Reviews

Laura on 2026-04-11 (5 stars):
I made this and it’s very good. I cut the butter a bit and used some garlic infused oil as well and I had some leftover Spanish red wine and used that instead of white. A different almost Bourgogne take. Very good, I’ll make it with white next time.
Bex on 2026-02-01 (5 stars):
I love French onion soup and this is a lovely recipe. Not sure it's worth the trouble, but that's not the recipe's fault as it's quite traditional. I'm not a wine person but it needs something so I added a dash of oak sherry that I keep for baking. I froze it in portions and have it for lunch with a grilled cheese sandwich, when I work from home.
Sara on 2025-12-29 (5 stars):
Fantastic recipe. My family and I thoroughly enjoyed it. The slightest of alterations that I made was I used gluten free flour because my son has allergies, red wine instead of white because that’s all I had and dried thyme, again all I had. Brilliant recipe. Delicious with no leftovers.
Madison on 2025-12-22 (5 stars):
This is a lovely recipe. I was skeptical about the toast, but it is easy to eat and delicious! I prefer it now over the soggy bread. This is going into the dinner rotation at the same level as our chili nights; and that means a lot to us. Thank you, Nagi!!
Tam on 2025-09-23 (5 stars):
This was such an easy recipe to follow. Absolutely delicious, will be making again.
Laura on 2025-09-10 (5 stars):
Such a great recipe. I used my homemade chicken stock. I also didn’t have any fresh thyme so I used a couple teaspoons of freeze dried thyme and put it in a coffee filter tied up. Another great recipe from this site.
Aida Pottinger on 2025-07-29 (5 stars):
Delicious! However 3rd option for onions is AirFryer for 30 minutes till they are soft and just starting to colour then finish off on top of stove for the last 15 (for when you don’t have a 10 hr time frame) I used 175° and tossed every 10 minutes.
Ai on 2025-07-14 (5 stars):
have made it a bunch of times, even (dont tell anyone) with pork stock, with ANY stock I have (ok, havent tried the fish one yet) - it is all delicious
Michaela on 2025-06-22 (5 stars):
OMG! This is a great recipe (my second from your site - did the Artisan bread - also amazing, I have made my own bread ever since!). Anyway, awesome. I used raclette cheese for the toast and it was hmmm hm!
Sara on 2025-06-22 (5 stars):
Onion soup freezes really well in my experience, I batch cook it and freeze it every year. More onions does increase the cook time substantially though and it needs tending to (stirring). I also add sliced garlic and a twig of rosemary if I got it in the garden and brandy if I got some.
Debra Grogan on 2025-05-18 (4 stars):
I made this last night and the onions after caramelisation were delicious. I used the Maggie Beer stock as suggested, but felt that the cinnamon in the stock overpowered the whole dish. I tried to balance it out but nothing worked. Next time will definitely use different stock.
Deb on 2025-05-17 (5 stars):
This soup is absolutely delicious and definitely foolproof lol....... I am a very average cook at best but this turned out so well. Thanks Nagi x
Muthulakshmi S on 2025-04-30 (5 stars):
this is my partner's favourite soup, and I make it every birthday. never fails. I sub the white wine (I am too lazy to buy it) with white wine vinegar + water, and I prefer it since there is plenty sweetness from the caramelised onions anyway. solid recipe, highly recommend
Kelly on 2025-04-28 (5 stars):
I forgot to rate. This was soo good.
Julie on 2025-03-01 (5 stars):
I used this as a basis for Apricot Chicken. Outstanding!

French Onion Soup

Rating

Keywords

Ingredients

Categories

Cuisine

Steps

Nutitrion

Reviews