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!
HI Nagi – I live in Brisbane and although the onion soup recipe looks great, the first thing I would make is your risoni with the Bolognese sauce. It was so good – and quick to make. Perfect mid-week meal!
I am in America. I have one piece of Chasseur , the panini grill in French blue and it is beautiful. I am sure it would like to have a cousin to keep it company in my kitchen.
Forgot to tell you I’m from America.
I will make your Onion Soup because it is my husband’s favorite. He contributes by peeling the onions because I’d be crying all over the place if I peeled them. I would also make my mothers recipe for Hungarian Stuffed Cabbage, so good!
I’m from Ballarat in Victoria and the first thing I would cook in it would be a hearty chicken curry, slow cooked with lots of creamy sauce to mop up with crusty home made bread.
Hi Nagi,
I am from the Central Tablelands in New South Wales, Australia. I would definitely cook my favourite comfort food that I just can’t seem to go a week without and that is you delicious slow cooked beef ragu. TO DIE FOR!
Hi Nagi!
I live in Canada. I’ve enjoyed your recipe blogs and now that you’ve posted a recipe for my all time favourite soup “French Onion Soup”, it is what I would christen the Chasseur with (if I win). I will keep my fingers crossed!
PS Please say hello to your mother for me. I told her how happy I was (and the rest of my Japanese family) that she had started to share her recipes with us!!!
Hi Nagi.. I live in Perth, Australia. Would really love to win one of these french ovens. I already thinking of trying out recipes using it. First thing I’ll cook is guiness beef stew, then I’ll try baking chicken.
Thank you so much for the opportunity.
I’ve wanted a Dutch Oven for some time now so I’d probably make a meal with it starting with dessert like an upside down cake; clean it then bake a hearty stew
Hi Nagi,
French Onion Soup is so delicious – the very best I have ever eaten was in Japan funnily enough! Even though I love it so much, I’ve always been too chicken to try it at home – I think I’d be devastated if I stuffed it up…But you have inspired me to give it a go! 🙂
I am from Rockhampton, Queensland and think FRENCH ovens are the most beautiful of all cookware…so elegant, yet heavy and resilient. The first meal I would cook in a new french oven is your Beef and Guinness Stew and then a Beef Ragu.
Looking forward to the week of French cuisine! 🙂
I want to fix your recipe for French Onion Soup. One of my very favorites. I don’t have the correct pot in which to make it. This would be perfect. I am in Windsor, CA
I would like to cook a traditional Indian goat curry as I have never had it but using great herbs and spices,wow what a feast for the family.I live in Australia
Loved the Wonton soup, so did the wife.
I’d make a nice stew or pork shoulder in my new Chasseur cast iron casserole pot.
thank you
I live in New York, United States. The first thing I would make would be lentil soup! Thank you for such a great giveaway opportunity!
Hello, Nagi, I live in Lake Tahoe and cook a lot of soup and bean dishes in the cold winter here. The dutch oven would be perfect for those. I would try your onion soup right away. The shallow pot would be fantastic for dishes I make starting with rice or risotto, adding veggies and chicken. Thanks for all your recipes! And now a chance to win one of these beautiful pots!
I live in California, USA. Beef stew would be first on my list!
Hi Nagi, I am from Melbourne and the first thing I would like to cook would be a Hungarian Goulash followed by an apple crumble.
I am right here in Melbourne, Australia as you would already know. These pans are absolutely stunning to look at, in fact the powder blue is on my Christmas wish list too. Hope I get lucky this time. Apart from trying out this fabulous onion soup, I already have a Guinness curry recipe that I want to experiment with…..a fusion of sorts drawing from the vast French and Indian cuisines.
I’m in America – Pennsylvania to be exact. Your French Onion soup looks yummy, so it would be a choice between it, a great Italian peasant soup or seafood gumbo. It’s that time of year!
I’m in NSW, and I’d make Beef Cheek Bourgignon in the Dutch/French oven. A long, slow, low cook makes those dense, meaty cheeks just melt in your mouth!