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
Hungry for more? Subscribe to my newsletter and follow along on Facebook, Pinterest and Instagram for all of the latest updates.
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!
Hao Nguyen says
I’ve never cooked using cast iron except on campouts with my son’s boy scout troop using a dutch oven over coals.
I’m from the United States, and if I’m selected, I would probably make either chicken curry or butter chicken with the Chasseur pots.
Cheers.
Kelly L says
I live in the US, and the first thing I would make, would probably be my winter favorite, my version of New England Clam Chowder!
Janice C says
Now I’m starting to feel the chill of a Canadian fall on my heels, the rich, fall off the bone goodness of wine braised short ribs, no doubt in my mind 🙂
Janice from Vancouver BC
Patrick Siu says
I’m in canada and i would make lamb shanks
bill boyett says
I am inspired to make some french onion soup.
Terry Terreteta says
I live in the USA. If I was to win,I would first make this French onion soup.These pans would get a very good work out.Nagi I make a lot of your recipes.My family just enjoys most of them.
Jacqui Bellefontaine says
Im in the Uk and I would love to cook sourdough bread in mine, soon followed by beef carbonnnade . Ive always wanted a set of the cast iron pans but sadly I still haven’t got one. Just love the pastel blue colour.
Judy Krist says
I live in SW Ontario, Canada and it is time to start cooking more hearty fare!
I would start with the Guinness stew!!!
I would be delighted to receive either of these truly beautiful pots. Thank you.
MaryB says
I live in the US and I would love to do some lamb shanks in one of these beautiful pots.
Wayne Wildman says
I live in the U.S. and I have always wanted to make French onion soup, so that is the first recipe I would try in my new French cast iron cook ward
Marilyn Roosen says
I have been making French Onion soup for years, since a teenager actually, and I’m now 56 years young! Unfortunately I had to give up the bowls I used to use in the oven to an ex. These pots (too plain a word for these awesome masterpieces) would be so well-used!
Gwen Mullet says
Nagi: I have truly enjoyed trying your recipes. I find myself constantly downloading recipes from various sites, but yours is the only one I keep coming back to. My husband is thankful, too! I am undecided if my first dish in a Chasseur would be your meatloaf in red gravy or this French onion soup. Thanks a ton for all the great recipes. Gwen, from USA
Martin Daynorowicz says
I live in USA and what first comes to mind was a cassoulet or coq au vin in the large one; and jambalaya in the shallow one.
Cindy Holowach says
I live in Canada and would love to make a traditional beef stew in this casserole pot. I have just recently discovered your website and really love your recipes and the puppy pictures!
Audrey Tobin says
The first thing I would make is Coq au vin. I would truly love to win one of these. Thank you for sharing a part of with us.
Reema says
Hi Nagi, lots of love to you from America. I made your vegetarian Mexican lasagna last night and am currently enjoying leftovers for lunch!
If I had a Chasseur pot, the first thing I’d make is chicken biryani.
Gene Zipperlen says
Hi, Nagy. I’ve enjoyed your emails and the great recipes. I will cook osso bucco if I win one of the casseroles. I live in Texas, U.S.A.
Gene Zipperlen says
So sorry to have misspelled your name, Nagi. I’m so embarrassed. GZ
Colette Bowdish says
I would cook my husband’s favorite, a hearty beef chili. As winter approaches here in Colorado (USA), my heart and tummy turns to warming soups, and stews, hearty chili among the favorites. Nothing cooks it better than an excellent pot. Simmering, bubbling and smelling oh so delicious when the lid is lifted for a quick stir when a whiff of warm, tempting steam hits your face and nostrils! I can hardly wait.
Rachel says
I live in the U.S. and if I had one of these gorgeous pots, I’d be making a tasty beef stew as soon as possible!
Stalenhoef says
I am from the Netherlands and I think that the first thing I’ll make in the shallow pan will be a Tarte Tatin .