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 am in America. If I had one of these I would definitely have to make a Guinness stew! That is so delicious and one of my favorites.
Definitely beef and ale stew. It’s always scrummy.! I’d invite friends round so that they could admire my new casserole dish
First cook in my new Chasseur would be Beef with Burgundy! This onion Soup wont wait, must try this week! I live in the United States.
I Live In The UK …
If I Won The Deep Chasseur Casserole Dish, I Would Cook My ‘Famous Recipe’ For ‘Mousakka’ …
Everyone Who Tastes This Thinks, It’s The ‘Best’ They Have Ever Had …
It’s My ‘Own’ Recipe And I Must Have Cooked It, Well Over 200 Plus Times If, Not More As, I Receive ”Requests’ From Family, Friends, Friends Of Family Etc. Etc…
So, It Would Be ‘Amazing’ To Have, A Piece Of ‘Cookware’ Of This Superb ‘Calibre’ …
It Would Defintely ‘Complete’ My Cookware And Take ‘Pride Of Place’ For Sure …
Thank You …
Trish O’Sullivan
The first thing I would cook in my cast iron casserole pot is an old fashion beef stew
I am in the US and I would make a beef and olives stew, theses pots are just lovely!
I’m in the good ole U.S.A. and I’d certainly be making that delicious soup as my first meal in that awesome french oven.
USA. Been wanting to make a milk braised pork loin. This would be the ideal pot for this dish!
These pots look fantastic! I would make my mothers pasta e fagioli!! I am in the US but love your world tours! I can not wait for the Crème Brulee!!
I live on the West coast of Canada. The first thing I would make would be my slow cooked Beef Stew. We raise our own Angus Beef and grow most of our vegetables so can you imagine how good that would be !
I live in the United States. I would be delighted to win either one, they look beautiful. I would surprise my husband and make your recipe of French Onion Soup. He loves onion soup and hasn’t eaten it in years. It would make him one happy hubby and I would be one happy wife.
I would make a beef stew
I’m from America and would most definitely cook your French onion soup!
i am in the USA and can think of so many things to cook in a chasseur pot… Julia Child’s Boeuf Bourguignon; French onion soup, red beans and rice, all kinds of soups and stews.
Nagi, thanks so much for the French cuisine tour..yummy. Can’t wait to try the French Onion Soup. Also thanks for the give-away..such great cast iron pots. Would definitely make Guiness Beef Short ribs, our favourite in cold New England winters in Massachusetts, US. But I would love to try Alcatra, a Portuguese beef roast from the Azorean Islands , where my grandmother was born. And the shallow pot great for Shrimp Mozambique…getting hungry just thinking about them! 🙂
Love your recipes, they are awesome and have contributed to my “travel around the world” cooking recipes on hand.
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I am in Germany and I would love to cook Osso Buco Milanese at first in this wonderful cast iron cookware.
I live in the good old USA. I would make my Boeuf Bourguignon recipe. Yum. I do make my French Onion Soup like you do very simple but extremely flavorful. I’m getting hungry just thinking about them.
Spain here. First choice to cook in the casserole: the French Onion Soup. We love our national and provincial dishes, but we do admit that our neighbours have some nice contributions to offer!
I live in the USA. The first thing I would make would be Irish stew.
I’m in the United States (New York) but originally from New Orleans so the first thing I’d make would be a delicious, Southern style jambalaya with seafood and chicken.