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 America. California to be exact. I am loving your website. Lots of great recipes.
I would like to try the Coq au Vin. It looks really good. Dinner party good.
I live in the US and after reading this, I need to make French Onion Soup. I’d also love to make a sweet potato casserole.
Wow, what a wonderful & generous giveaway! I live in America & I’d use my pot to make either this French Onion soup or the Coq au Vin recipe, first. Yum! Thanks for the chance.
HI Nagi, I live in the U.S. – Pennsylvania to be exact. I just discovered this website two weeks ago and have already made four different things and so far have loved them all. Last night we made Spicy Korea Pork Stir fry. Your recipes are great and easy to follow. I was running late last night and my husband ended up making it. It came out perfectly. He even took a picture of it. Anyway, so many wonderful things to make but I would try your Chicken in cream wine sauce first , or french onion soup, or stew or ….. I am trying at least one new recipe each week, so if I am lucky enough to win there maybe a new great recipe you posted I will want to try.
I live in London, UK and love your recipes! The first thing I would make is a slow roasted tomato sauce!
Hi, Nagi! I’m Colleen, and I live in Kalamazoo, Michigan, USA. If I had that fancy pot, I would give it to my Mom. She makes the best pot roast! (But she has awful pots.). Yum–Fall comfort food!
I’m from American, Houston TX I’d love to win the Chasseua cast iron shollow pot. I’d love to try your French Onion Soup.
Hi Nagi, my name is Margo and I live in Bedford Nova Scotia Canada. This is my favourite colour and it would not only be so useful in my already Tiffany Blue kitchen I would also place it in a prime location for all to see and admire. My first recipe to make would be your delicious French onion soup. I am going to try to make it today without this special pot, probably won’t be as delicious as it could be, but I will imagine that it is being served in your pot.
Thank you for sharing your lovely recipes.
Margo
I live in Lak Echo, Nova Scotia Canada. I would love to win the Duck Egg Blue Chasseur cast iron casserole pot. The first thing I would make in it is cioppino. Yum
Hi Nagi!
I live in Australia and would LOVE the casserole pot to make braised beef short ribs!!
I’m a big fan of your site and all of your recipes! I’ve tried 4 of them so far and can’t wait to work my way through the rest!
Hi Nagi
I’m a recent fan of your recipes but am now cooking them at least once a week.
I live in Redland Bay, Qld, Australia
I would make a Chili Con Carne with my new pot.
Hi Nagi,
I live in Lockwood South, central Victoria Australia. I would love the Chasseur Cast Iron casserole pot in Duck Egg Blue and the first thing I would cook would be lamb shanks. Mmm lamb shanks…
Hi Nagi, I live in the western suburbs of Sydney, NSW. For slow cooked meals like your beef cheeks and lamb shanks recipes I’ve made do with a dodgy cast iron Dutch oven I bought in a supermarket, but have always dreamed of one day owning a fair dinkum Chasseur. That would be amazing! The first thing I would cook is this wonderful French onion soup. It only seems right!
Hi Nagi, I’m Dorothy and live in Dunfermline, Bonnie Scotland. Love your recipes. Made your Honey Lemon Chicken for Mr Fussy and he thoroughly enjoyed it and because of your fab recipes I have fed him I may have to find another nick name for him.
If I won one of the prizes I would make a chicken chausseur.
lamb shanks for me, a favorite dish for anytime!
Hi Nagi,
I live in Australia and without a doubt my first dish would be lamb shanks as hubby loves this and I have tried other dishes with little or no success. He would love you all when I do it, lol.
Hi Nagi!
I live in Canada and I would love to make a classic Boeuf Bourguignon in a proper vessel! I love the rich red wine sauce and tender meat.
Thank you! Love your blog!
Andrea
Hi Nagi,
I live in Australia.
When I saw the Chasseur pot I immediately thought of Sri Lankan Ox Tail Stew made to a traditional recipe. It’s so full of flavour with rich, thick gravy. It’s a bit like other ox tail stews but better! And of course it is best cooked in a solid cast iron casserole.
Cheers,
Richard
Country: USA
First thing I’ll cook: Kaopoon (Laotian dish) – rice vermicelli with red curry chicken soup YUMM!!
Hi Nagi:
I love RecipeTin Eats. Your recipes are not only delicious but your directions make complicated steps so logical and easy to follow. I made your Guinness Stew and just purchased lamb shanks to make your recent recipe. I have also made your Indonesian rice dishes. Every one of your recipes has been a smashing success!!!
We live in Austin, Texas in the United States – just moved here from Chicago. I would love to make the French onion soup in the Chasseur Cast Iron Casserole.
Hi Nagi, I’m Adrian from Australia. The weather’s warming up but I’d be putting a Chasseur through its paces by slow cooking a hearty oxtail soup in it!
Cheers,
A.