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!
I would make a chicken curry I’m in QLD, Australia.
Hi Nagi,
I’m in Australia and I would use one of these stunning pots to make good old fashioned chicken stock. I love nourishing my family and the stock could lay the foundations for so much healthy deliciousness!
Tammy
Australia
Lamb shanks
Thanks
I live in Australia and I would love either of the Chasseur pots! I would make a thick and rich chilli con carne or maybe shredded chicken with adobo chipotle sauce *drool*
Hello Nagi,
I am from the US and would love to win the French Oven!! The first thing I would make would be Grandma Burger Chicken (named after my grandmother, of course). It is a simple one pot meal but the key to having an amazing version is the right pot with a tight fitting lid. I intend to make your French onion soup this rainy weekend coming up. I am excited to try this simple yet incredible looking recipe. Wish me luck!
Thank you!
I am from the U.S. I would love to win one of your wonderful and beautiful-looking Dutch ovens. I would make a delicious beef stew which is one of my husband’s favorite dishes.
Australia ?
I would cook a Lamb stew in the taller of the two pots if I won. Soon after I would make your beef cheeks as a casserole….. They we’re soooO delicious!
MaybelLamb shanks, osso buco?
So many meat things!
THenI would portion them up for the freezer so I can eat well over the next few months without overheating the house during the summer meltdown.
I have silver side on hand right now, but, the slow cooker takes care of that.
It would be great to have a casserole pot again. The cast iron, unsealed, favoured the food to much, so I cleaned it up and gave it away. i
I live in Perth – Western Australia. I would love to win the prize because I currently cook with very low grade saucepans. To experience a ‘Chasseur’ cooked meal would be bliss. I would pay homage to the Chasseur saucepan by cooking Chicken Chasseur. What a classic dish for a classic saucepan.
Hi Nagi,
Thanks for so many great recipes! I’m from Australia and these prizes look fantastic. Thanks for the opportunity to win such amazing cookware. I have never been able to afford to buy them myself but a girl can dream!! If I finally got my hands on one of these beauties I couldn’t go past trying out your port braised lamb shanks – DELICIOUS!
Hi Nagi
I am from beautiful Vernon, British Columbia Canada and would love to win one of your pots. Depending on which one I would make your butter chicken or your French onion soup. My daughter and I love your site and make your recipes on a regular basis. Thanks for all you do to encourage great, from scratch cooking at home.
Oh, I absolutely love that baby blue color! I’ve never cooked with Chasseur, but they look beautiful. The obvious answer on what to make in a casserole dish is a casserole :), but I’d also love to make some curries and soups. Today was our first real fall day here in Kentucky (oh, I’m in America!), and I could not be more excited to get into soup season!
I live in NY, USA and would love to win one of these Chasseur pots, they match my kitchen perfectly! The first thing I would make is chicken cacciatore. I made the Coq au Vin recipe you posted the other day and it was delicious! I would love to make that again in this pot as well. Thanks for the chance to win!
Hello from the US!! I would definitely make a stew in mine the first time I used it!! I hope I win because a Dutch oven has been on my list forEVER!!
OH my goodness! I would love love love to win one of these pots. I am in the USA and these pots are not in my budget just yet. Though I have been fantasizing about them for years. My first dish will be French Onion Soup, now that I know this type of pan is the key I’ve been seeking!! Then, Coq au Vin. Then Boeuf Bourguignon. I use Gourmet’s Basic French cookbook and compendium by Louis Diat, 1990 edition. This book has been patiently awaiting one of these pans, so we can really put it to good use!
Hi Nagi. In the Dutch oven I would make your chicken and sweetcorn soup. It has been such a favourite this Winter. I planned to try more soups this past Winter and your recipe is the favourite particularly with our fussy 9 year old. She says “Mum this is a ‘make-again meal’. So its a winner for sure. Personally, I love the Cream of Chicken Soup with the flavour base that does so many other meals too. Now, for the shallow pan – well, last night I made the Honey Mustard Chicken. Hubby said “Oh, have you tried the chicken? It’s so moist”. Even after seconds he said he could eat more. Plenty of sauce and plenty tasty. The spaghetti and meatballs, one pot lasagne, mac & cheese, then spinach & ricotta one-pot would be good and just about anything that just is pan-fried with a delicious sauce. I’m from Sydney and absolutely love your blog, recipes and also read SFI. Love Jenny (PS I really need to practice cooking rice as it never turns out for me – too gluggy !)
I am from Port St Lucie, Florida USA. If I won the casserole dish I would make your seafood gratin pasta bake and would definitely make the French Onion soup if I won the Duch oven (although I don’t think I can wait that long before I make it)
United States. I would make potatoes dauphinois.
I’m from AUSTRALIA
I will cook lamb shanks
Hi Nagi –
I am from Winnipeg, Manitoba – Canada. With the shallow Chasseer dish I would make your creamy chicken in white wine sauce and bacon. It looks so good and decedant! If I get the French casserole Chasseur then I would make your french onion soup. Our winters can get pretty cold here ( -40 degrees Celsius) so making french onion soup will definitely help get through it 🙂
I also want to say that I love all your recipes! You have inspired me to start my own blog and it’s just encouraging to see how you pursued it
Thank you!
Hi Nagi! I’m a huge fan from California, USA. French onion soup is always my indulgent guilty pleasure so this recipe is gift from the heavens!
If I were to win, my definite go-to would be ox-tail stew, a taiwanese-french fusion that mixes my mother’s traditional recipe with a good measure of french techniques! ^^