French Onion Soup is essentially caramelised onion in soup form topped with cheesy bread. The French are genius!
Caramelising onions calls for patience, but it’s worth it. You’ll be rewarded with deeply golden, intensely sweet onions that forms an incredible flavour base for this French Onion Soup. For an effortless option, see how to caramelise onions in a slow cooker!
THE ICONIC FRENCH ONION SOUP!
French Onion Soup is probably one of the most epic soups in this whole wide world. And yet, the soup itself is made with very few core ingredients: butter, onions, flour and stock/broth.
The magic is in the caramelisation of the onions, cooked slowly for at least 40 minutes. And of course the crowning glory – the glorious melted cheese toast!! Because let’s face it – French Onion Soup without the cheesy toast is just onion soup. Meh!
CARAMELISED ONIONS – STOVE OR SLOW COOKER
The caramelised onions are the star of the soup (well, on par with the cheesy toast). Making caramelised onions the classic way on the stove takes upwards of 45 minutes for a giant mound like we use for French Onion Soup.
It’s not high-stress or high-energy effort. For most of the time, the onions are cooked over low heat so you just need to stir them every now and then.
It’s the sort of thing that’s good to make while pottering around the kitchen doing other things. My cast iron pot is 24 cm / 10″ wide and it was full to the brim with raw onions and took almost an hour to caramelise. If you have a wider base pot, it will be faster – probably closer to 45 minutes.
Though of course, if this all seems like too much effort for you…… introducing….
SLOW COOKER CARAMELIZED ONIONS!!!
Yes. You. Can!!!
I first learned of this from a reader then found this recipe on TheKitchn. Terrifically convenient and totally hands off, just throw the onions in, drizzle with butter or oil then leave on low for 10 hours.
This will get you 75% of the way there. The onions are browned a bit but lack the same intensity of flavour you get from caramelising on the stove.
So you do still need to cook the onions on the stove for 10 – 15 minutes to achieve the same true flavour. And while one may wonder what’s the point, there’s a big difference between cooking down onions for almost an hour on the stove vs 10 minutes.
Plus, no having to man-handle a gigantic mound of onions in a pot that’s too small (me, me!).
THE REST IS EASY!
Caramelised onions aside, the rest of the soup is effortless. Get all the tasty brown stuff off the bottom of the pot by deglazing it with a touch of wine. A touch of flour to thicken the soup every so slightly, a LOT of broth, and an optional sprig of thyme and bay leaves.
GOOD BEEF BROTH IS A MUST!
If you use store bought, which I often do, use a good quality beef broth/stock. I personally do not recommend any of the mainstream brands sold in Australian supermarkets. I use Maggie Beer and Moredough from Harris Farms (I stock up when it’s on sale!), or private labels from butchers.
If you can’t get good quality beef broth, use chicken or vegetable instead. I find that the quality of those by mainstream brands is much better than the beef stock. The beef is fine to use in things like gravy and stews, but not when it’s a key ingredient like in this recipe.
DON’T HAVE OVEN-PROOF SOUP BOWLS?
Neither do I! Can’t justify the storage for ONE soup that calls for it. Sure, it looks thoroughly dramatic to be served a piping hot bowl from the oven with the entire surface covered in bubbling cheese (and a piece of bread under there somewhere).
But actually, I prefer making grilled cheese separately and popping them in the bowl because the bread isn’t as soggy from absorbing the soup by the time it gets to the table.
And lastly, a little tip – try the grilled cheese with your very own homemade Artisan bread. It is mind blowingly easy and has been wildly popular with readers since the day I shared it! – Nagi x
FRENCH ONION SOUP RECIPE
WATCH HOW TO MAKE IT
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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
Cheesy Toast
- 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)
Instructions
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.
Recipe Notes:
Nutrition Information:
COMPLETE YOUR FRENCH MENU!
Pan Fried Fish with Brown Butter Lemon Sauce (Totally French! Poisson meunière)
Garden salad with French Vinaigrette
Chocolate Mousse (classic French)
LIFE OF DOZER
I KNEW I’d find a use for those onion goggles one day! 😂 (I don’t need them, I wear contacts so I’m onion-proof. Gimme all the onions to chop!)
French Onion Soup recipe originally published in September 2016 as part of a Chasseur cast iron cookware giveaway. Since this time, the recipe has evolved (adding more flavourings – wine, thyme and bay leaves) so new photos, words and recipe video added!
French Onion Soup is my all time favorite, any time, anywhere, but I have never had the proper vessel to make it at home so it would be first.
Karen
US
Hi Nagi! I’m from Australia and here is my entry ;
Chasseur Chasseur oh how I love thee,
Duck egg blue or white you are so very pretty,
If I won, either colour would be received with glee!
First dish I would whip up is Nagi’s salmon risoni,
Creamy and dreamy it’s a favourite in my family!
Ooh I’m from the US and something decadent to make first would like a beef bourguignon!! Now that we are getting into the fall season. Comfort food!
Hi Nagi,
I live in Florida in the United States and love your blog. I would love to try cooking Lamb Shanks, but I would first make my mom’s cheese soup I haven’t had that in years since she last made it and this would be my first attempt.
Thanks
Hi Nagi
From Coventry United Kingdom 🙂
Oh first thing if I win, I would keep it in my display cabinet ? Haha
I’d love to cook prawn and pineapple green curry Malaysian style ? It’s gonna be spicy creamy and absolutely delicious finger licking good trust me. Serve it together with fluffy steam rice. Oh my now im hungry. OK gotta cook. See you later alligator and don’t forget to send me them chasseur thingy ?
Hi, Nagi!
I’ve never had french onion soup before … so that would definitely be the first dish I cook in the ‘french oven’. I’m from Victoria, Australia 🙂
Tammy
I’d love to try making that artisan French bread that’s baked in a Dutch (French) oven! I’m located in the United States.
Thanks for the chance to win!
Hi Nagi,
I’m from Melbourne, Aus. I would either cook your French Onion Soup (which looks amazing, and is something I’ve had mixed success with before!) or my favourite dish to cook in a French (Dutch?!) Oven which is Chicken with Forty Cloves of Garlic! Missed being able to make that since I left home a few years ago and don’t have my own pot…:(
US, i want to make French Onion soup since it is my hubbys favorite ?
I’m from Canada and the first thing I would make is a big stew, one of your recipe of course !!
Hi
I am from Vienna, Austria
I would try an onion soup and beat for my first cooking in it, if I were so lucky to win that.
I live in the U.S. I would love to win this! I so need it!! First think I’d make is french onion soup.
Hi Nagi
I’m from Rockhampton, Queensland, Australia the beef capital. I would make my families favourite of Red Wine Ragu. Beautiful dish in a beautiful dish.
Hi! I’m from the United States of America ?? In all honesty, I would probably make a pot of chili! ”Tis the season.
Let me know if you have any good chili recipes!
Also, how awesome is this contest?!
Heyyy!!!! I’m in the United States and I always wanted one of this pots ..it’s gorgeous!! I would be making a nice and tasty sancocho??
Hi Nagi! USA California ❤️ I would make French onion soup! I’ve never made it before so I think that would be s good place to start.
Hi,
I’m from Canada.
I would love one, never owned anything like it. Love your recipes and hopefully I can expand my cooking.
Australia
I would make red wine lamb shanks ? A fave i our house!
Australia, Melbourne. I would make a baked chicken and leek risotto in my duck blue Dutch/French oven, yum.
Hi Nagi!
My name is Erica Jordan and I live in the USA! Your site has been the saving grace of my husband! My husband and I recently moved to Virginia from Dallas. My husband recently found out he was pre hypertension and I knew our nights of restaurants with mystery ingredients had come to an end. Your recipes have helped so much and my husband knows now that he can have heart healthy meals that kick serious butt!
If I am a lucky winner, I would make your delicious French Onion Soup!