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!
oh, mannnnnn!!!! That French Onion Soup looks so awesome. That’s probably the first thing I’d make!! I’m in the US.
I love your site!
French onion soup, for sure. From the US.
Hi Nagi,
I’m a student from Denmark, which is a small country in northern Europe (not sure how many knows it). I’ve followed your blog for quite some time and I absolutely love your attitude towards food, though it is kinda confusing when you make me want stews and its like in the middle of our summer here. The first thing I’d make would probably be your Guinness stew as the cold is creeping in on us here in the north!
– Katrine
I am in the United States and I would love to try out the French Onion Soup. Or Maybe a Spicy Chicken Enchilada Stew with crispy tortilla strips and cojita cheese.
Southern California (USA) here. I just might have to make that French Onion Soup. I’m drooling looking at the pictures.
I’m from the US. I would love to make your French onion soup!!
I am in America and winter is approaching quickly in the north! I would make a delicious stew: meaty with ymmy veggies and taters and a sauce to die for….or being Czech: a sauerkraut and sausage (with green peppers of course)…making me hungry!
Nagi,
I live in the United States. I think for my first dish I would cook a roast chicken with vegetables. I can imagine that these cookwares would make an incredible whole chicken. I’ve always felt too intimidated to cook a chicken as I am afraid it will dry out. I’ve always felt that if I could cook a chicken well then I can cook anything. 🙂
Love your blog and keep the yummyness coming!
Hi, I live in Canada (Nova Scotia?) and the first thing I would cook is your French onion soup, your recipe looks delicious! Thanks
I’m from the United States and that French onion soup looks amazing, so that’s what I would cook in it!
I’m in Melbourne (love my home town!) I love to cook and would especially love to cook with one of these beauties. I’d make lemon risotto – I’d happy stir my risotto in my new dish for hours!! Oh how I would love to watch the rice go round and round in that lovely dish!!
Hi from Canada….definitely good old fashion Pot Roast with root veggies…YUM!
Hi Nagi, a good sized casserole would be ideal for the festive ham, first eaten warm, then with a good potato salad and finally into a warming ham and veg pie. I am from the midlands in the UK and I am just thinking about attempting a French night, thank you for your inspiration.
I live in he United States and I’d love to make a pot of Pork Chili Verde!
They are gorgeous! I’d cook Tarragon Chicken – it’s spring, the tarragon is about due to come back to life in my garden and I wait all winter to make this dish 🙂
I’m in Far North Qld, Australia. I am wanting to try an Indian style curry after tasting an authentic Indian dish from some new friends! Would love to master the art myself ?
Australia
Chilli con carne
I live in America and I would definitely make that French Onion soup! Thanks for the chance to win. 🙂
Lamb shanks and pearl barley soup!! Me please!!!
And I’m in Australia!
??? Eye roll….I KNOW….. ?
Hi Nagi
From Victoria Aust. I would make a pumpkin and coconut curry soup!