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 have always wanted to make French onion soup but never have and yours may have just inspired me. It looks amazing! As do these French Dutch ovens! Live in USA and would make soup in them for starters!
I live in the USA. I would have to make the classic French stew into is beautiful pot, beef borguinnone.
I live in the U.S. and I think the first thing I would make would be cabbage rolls.
Hi Nagi! What a delicious week you have planned! I haven’t made French onion soup in ages! Here in the American South fall has not started yet but, as you know, that doesn’t stop me from making hearty food! It would be a real toss up as to what I’d make first in a Chasseur pot…so many choices, but I think I’d have to go with Coq au Vin (with a nice crusty loaf of French bread of course). PS that French chef looks as good as his food! 🙂
The perfect 85th birthday present for me. I’ll make beef bourguignon topped with puff pastry. Umm>
i’m from North Carolina USA.
I live in the US, and it’s nearing the end of Vidalia onion season, but I have found a bunch. I would love to make some Vidalia onion soup with the Chasseur pot, but first I would like to make my own chicken and beef stock which would make the soup even more flavorful. I love your recipes! Thanks for this contest.
I live in the US. Would love the shallow casserole to make one pot dishes.
I live in the U.S. I’d make my family’s Italian Pot Roast. It is one of my Dad’s favorite meals. Mom passed away two years ago, and Dad is still going strong at 90. I’d invite him over for dinner and he’d know immediately upon entering the house what’s for dinner just from the wonder aromas!
I’ve tried to make the pot roast in a crock pot, in the oven and in a pressure cooker, but it still comes out best when cooked low and slow in a dutch oven on the stove top!
I live in the US and have a recipe for short ribs that calls for cooking in a dutch oven but I never had one! Would love one as we get into winter and more soups and comfort foods!
Good Morning! Thank you for your delicious recipes and the chance to enter the Chasseur giveaway! I reside in the United States and love Italian family style cooking.. Chasseur makes heirloom quality, beautiful looking pots that must be a joy to cook with. My Chasseur would be treasured and cared for and passed on to my daughter someday, hopefully used for generations to come. If I were the recipient of the casserole, I would make my Grandmother’s recipe for Italian Wedding Soup. The shallow casserole is perfect for making San Francisco style Cioppino fish stew. The magic ingredient is cooking with Chasseur cast iron pots. Thanks again!
Hi Nagi,
Laura from Toronto, Canada.
Love your site and recipes! We are transitioning from Summer to Fall and I have bookmarked MANY of your recipes for when the weather changes. I think when I win the GORGEOUS Chasseur pot, I will make the slow cooked beef cheeks first. I have been eyeing the recipe for a while. Thanks for the chance to win a dream pot, and all the wonderful recipes and detailed instructions, greatly appreciated.
This would be fantastic for making chili, but now I’m kind of in the mood for French Onion Soup! Thanks!
OMG OMG OMG All I need in this life is a Chasseur pot. My sister recently got married and they received 2 of them, and from that moment onwards I knew I just had to get married (just for the Chasseur pots!) If however I win this, then I don’t need to waste my days finding a husband! I am from Melbourne Australia, and I dream of slow cooking delicious beef stews consisting of mainly red wine. Even though winter is nearly over I will still make sure If I win this, then everything will be hearty cooked meals.
Hello from the USA.
I would use the shallow casserole to make the most scrumptious biryani to stay warm now that it’s getting colder outside
Hi Nagi
I’m in Australia and just love your website. As a 50-something male who is just learning how to cook, your recipes inspire me to have a go and give it a try.
The first thing I’d use the Chasseur ‘French’ oven/casserole pot for is this French onion soup – it looks absolutely delicious.
Keep posting your fantastic recipes!
Peter
Australia. Stew. Definitely meltingly soft beef stew. Even if summer is coming.
Hi Nagi, I live in Sydney and I would make my delicious Chicken Cacciatore in the pretty Chasseur casserole pot.
Hello Nagi and Dozer!
I’m from America, the Deep South to narrow it a little. If my mom was in town when it arrived, I’d cook French Onion Soup because it’s one of her favorites. If not, I’d try the Coq au Vin because I’ve never done it before and I’d like to add it to my dinner stash.
Sabrina
Nagi I’m from Australia!!!
The first thing I’d cook if I had a Chasseur pot is Ragu:) Then the next dish would be beef stew hehebe I think all the celebrity chefs like Marco Pierre always cook with these so they must be the best! I’ve always wanted to own one.
The French onion looks delicious 🙂
Will try soon I love your dedication to cooking and have learnt so much from your blog.
I am in Australia. I would make braised beef ribs as it would be great to be able to brown on the cook top and then put the dish straight in the oven.