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!
Hello Nagi and Dozer,
Greetings from British Columbia, Canada – The first thing I would make is “Winter Solstice Chicken Pot Pie” perfect this time of year.
Cheers
I live in Queensland Australia and the first thing I would cook would be the coq au vin!
Hello Nagi,
If I was lucky enough to win one of you Chasseur Cast Iron Ovens – I would take the Shallow Casserole. The first thing I would make is my Dad’s Coq Au Vin, or maybe Winter Solstice Chicken Pot Pie…….. so many to choose from
I live in British Columbia, Canada.
Love your Blog!
Hi Nagi. I live in Sydney.
I would use up the tasty pork cheeks in my freezer, making a low and slow casserole with big, bold flavours to compliment the succulent meat. Oh the thought is making me salivate!
From Queensland I want to say – I don’t want this pot I NEED it! It has been on my list for so long but just know I won’t be able to afford it. I would of course be using it to cook your French Onion Soup, many other soups and stews and my sourdough bread. If Dozer were to draw the winner I just know in my heart he would sniff out my entry.
He was a cutie and still is, a big woof Dozer.
Hi Nagi!
I live in the United States, and the possibilities of what I could do with one of these babies (FRENCH/DUTCH Ovens) are almost endless, but…. I LOVE your one pot mac and cheese with Broccoli and Chicken… I think that is the one. ((But the Guinness Stew is to DIE for…. and I have never made French Onion, and the pics are amazing!!))
Love Love Love your blog and your recipes! I LOL’d when I read about the food expo and your mom asking you if you were wearing false eyelashes… Aren’t moms SO the same no matter where they live??? Gotta love them!!
Hi Nagi! I’m from Melbourne Australia, and the first thing I would make in the beautiful blue cast iron pot (that I have been lusting after for some time now) is a classic beef daube. Why? Because I’m sick of having to use multiple pots when I make it currently! My casserole pot isn’t so great with browning meat and veggies so I have to use a frying pan; and then it has a frustrating tendency to stick when simmering for hours. And in the shallow white pot – your classic roast chicken that has been on my ‘to do’ list for months, but I just don’t have the right pot to do it in!
Hi Nagi,
I live in Sydney, Australia. I love this soup, thanks for sharing. I’d love to own this beautiful cookware and the first dish I’d cook using it would be a truffle risotto.
Laine
I live in the US… Hawai’i to be exact. 🙂 I would absolutely love the Chasseur cast iron casserole pot! My husband and I absolutely love French Onion soup. Your recipe looks scrumptious.
I live in the state of Arizona in the United States. The first thing I would cook is a traditional Puerto Rican Sancocho, which is a thick stew made with rooted vegetables and a variety of meats. This is the right pot to cook it in!
Hi Nagi, I’m in Australia. I’m thrilled you are contributing to Recipes magazine so I have coloured pics of your great recipes! I think I would like to cook your entire French menu for my friends who love everything French. We have just been out for dinner at a French restaurant and had FRENCH ONION SOUP which was delicious. I vowed to make it for them so that would be the first thing I would cook in the French oven if I won thanks for all the yummy recipes!
The first thing I’d cooked would be French Onion Soup because a classic needs to be christened with a classic
Hi Nagi, longtime subscriber here from Australia (Adelaide). I’d love to win a Chasseur Dutch oven, the first thing I’d cook in it is a slow roasted pork shoulder for pulled pork! I’ve found an awesome recipe with liquid smoke that looks amazing. Yum!!
Ps- I ADORE Dozer, he is the cherry on top of your posts. I’m a vet nurse in training and Goldies are my absolute fave. Just gotta find a rental that lets me keep a dog!
I live in the USA. French Onion soup is my favorite, so I would be making that for sure!!
I live in Oregon in the USA so we are starting autumn and the season for hearty dishes. I want improve my braising skills so I would start with Chicken with 40 Cloves of Garlic or Leg of Lamb with Potatoes and Carrots …. But French Onion soup is my all-time favorite soup so I would make that also. Thanks for your varied and excellent recipes!
I live in the US and would cook some of this french onion soup! Yum, one of my favorites 🙂
I’d make a mutton curry. A pound of meat, some chopped onion/garlic/ginger, a can of pasta sauce, a spoon or two of curry powder, oil & salt. Toss them into a dutch oven (like the one here), put the pot on low heat and go watch a movie. Et voila… you’ll be amazed at the magic done by time, heat, cast iron, and a few simple ingredients. Salut!
United States
RTP, NC
Lamb shanks, beef stew or this onion soup!
Would love to try the french onion soup recipe. Live in America. Thanks
Hi Nagi,
I live in the Blue Mountains not far from Sydney. In honour of your French week and Chasseur I would make beef bourguignon, Yum!