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’m live in your city – Sydney! I was looking for cookware on the weekend that can go into the oven from the stove which many of your yummy recipes call for (One Pot Greek & Lemon Chicken Rice for example) but hadn’t found anything of the right size or looks like it can retain heat well to give it that nice caramelisation except for the more pricey ones like Chasseur! I’ll be dancing non-stop (and I have two left feet!) if I win this! It’s hard to choose which I’d cook first!! Salisbury Steak with Mushroom Gravy is probably it as I hadn’t cooked this for awhile. Thank you, enjoy today’s sunshine!
Hi, I’m from the USA
The first thing I would cook is your recipe for Lamb Shanks and/or Osso Buco
Hi, I’m in Australia ! I’ve been dying to try to cook your fragrant coconut pot roasted chicken ! Looks so yummy I just need the pot 🙂
I live in the US (Honolulu) and the first thing I will make is beef stew, my family’s all time favorite comfort food! Thanks for the opportunity!
USA – I would definitely cook the French Onion Soup. One of my all time favorites. Or a shrimp and crab crowder.
I’m from Australia. Currently trying to perfect the recipes my Nonna taught me before she passed away – the first thing I would attempt in the Chasseur would be Nonna’s meatball recipe (slow cooked in homemade passata with pork ribs for extra flavour).
Hello Nagi
The very first thing
I would cook would by Guinness Stew. I have been meaning to cook it all winter (even thou its spring here in Aust still a few chilly nights) & even bought the Guinness, which I might add is still sitting in the cupboard ?. This French oven would definitely get me cracking to make it. Love your recipes, can’t wait for the French theme .
PS Pats & cuddles to Dozer?
I live in Canada; I would make definitely make that delicious French Onion soup in that lovely deep French (Dutch) Oven Casserole dish.
Bonjour Nagi from an unusually wet Dubbo in Central West NSW Australia. My first meal would be an Irish Stew with loads of farm fresh beef, home grown potatoes and Guinness. Bon Appetit
I am in Australia, and am freaking out at how perfect that duck egg blue pot is… I would cook chicken braised with leeks, fennel and broad beans every other spring green in the shallow pot… with herbed new potatoes… and in the large I would be making a spring green minestrone…
thanks for the opportunity… amazing giveaway!
Living in Pennsylvania in the fall calls for beef short rib
Now that it is getting colder here in Canada, I would love the casserole pot to make those delicious port braised lamb shanks. They seem like the perfect thing to make on a chilly weekend.
I would make Creamy Chicken in White Wine Sauce with Bacon!! I have always wanted a Chasseur but the price always scared me. Thank you for the opportunity ?
I have dreamed of owning one of these for ever and the first thing i would cook is lamb shanks…slow and tasty! yum!
I live in the state of Washington, USA and winter stews and soups are soon to be much appreciated. Thank you for this great opportunity and the many wonderful recipes you share
I live in the US. I would love to win the casserole pot! Coq au Vin sounds so good right now. It’s still too warm for soup where I live, but French onion is the all time favorite in my house. Good luck everyone!
Ahh, goodness. That looks delicious. I live in Georgia in the United States and I would first make an herbed risotto with lobster!
I am from Sweden and would make moules marinières <3
I live in Australia and the first thing I would cook would be…. OMG Lamb Shanks !!! Then I reckon my hubby would love this soup to try.. After all he does love French onion dip ☺️☺️
i live in the USA and the 1st thing i would make if I were to win the cookware is “braised beef short ribs”. Delicious!!!!!
The first thing I would make would be my beef pot roast with carmelized onions, red wine and rosemary..:) Thank you for this contest!