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 from Carlsbad, California (USA). I just made your terrific meatballs for dinner tonight. What wouldn’t I cook in my new casserole pot? Maybe that delicious looking Coq au Vin!
I’m in Sydney, Australia and I would make an awesome rendang in the French (Dutch) oven!! Fabulous blog by the way – you have a wonderful writing style 🙂
United States of America, I would make this wonderful pinion soup shown here. Wish me luck!
Hi Nagi! I’m from New York in the U.S. and I would definitely make Julia Child’s Boeuf Bourguignon, or your Garlic Risotto with Lemon Pepper Chicken. Love your blog, love your recipes!
Hi Nagi – I am from Melbourne Australia. I would definitely do beef cheeks in my new Dutch (French) oven – the Movida ones! I had a couple of Chasseur pieces which I loved a number of years ago but unfortunately the ex took them 🙁 So would love to have my own brand new cookware.
I’m from Canada.The first thing I would make is cabbage rolls.Thanks for the chance!
Since it is getting chilly here in New England, I’m sure I would have to make a soup/stew with a butternut squash/apple base.
USA and a hearty beef stroganoff for the upcoming fall/winter season!
I live in Milwaukee, Wisconsin, those pans are amazing and would make Creamy Chicken in Wine Sauce.
Oh man! What wouldn’t I make is an easier question! Now that it’s soup season, I’d make my favorite chicken tortilla soup and then I’d be on a chicken kick and would want chicken and dumplings. My husband would then request chili because he loves having leftovers to make chili dogs! I’d have to use the shallow one to make one of my favorite Lebanese dishes: green beans and tomatoes simmered with lots of cinnamon and allspice and served over rice. I suppose since they’re French ovens, I’d have to try this amazing French Onion Soup recipe you posted, too! They would get lots of use and lots of love in this American kitchen!
Hi Nagi, I live in Australia, Brisbane, and would love to make the French Onion Soup using your new Chasseur casserole pot. Next I would cook the Red Wine Beef Cheeks again. I always look forward to trying out your recipes and have had great success so far. Your blog is entertaining and the photos are so good you just want to try everything. Thanks so much 🙂
Hi Nagi,
Great blog! I live in Australia but I love a good beef rendang so that’s what I would cook first if I won these amazing Chasseur pots – they are super stylish! ?
Hi Nagi!
I’m in the Netherlands. I would-be make an enormous pot of Bolognese sauce, because honestly there can never be enough home Cooked pasta sauce in my freezer. Very eager to try this recipe too though! Love your blog 🙂 Greetings from the Netherlands!
Oh no, I made a typo in my email address with my previous comment! The email address I posted this comment with is correct.
Hi Nagi
I’m in England and still loving your email arriving in time for hubby to travel home from work and I’ve cooked your recipes for dinner.
We eat veggie so I can adapt them.
If I won, I’d cook GREEK STYLE PEAS-ARAKAS Latheros…. It’s a favourite….
But I’m going to try the course au vin with soya ?(and the crème brule… Im feeling more confident)
Cheers Nagi
Chiming in from Canada’s Sunshine Coast, just a forty-minute ferry ride from Vancouver BC. I would use the pot for curry something, actually curry anything! We’ve made lots of your recipes, and I’m a big fan of slow and simple home cooking, so would love to have a pot as beautiful and functional as these are.
A large roast beef. My mom had a set of cast iron cookware and made the best beef roasts. I just can’t get that flavor she could using the cookware that I have. Nothing like a good bowl of French onion soup. Looking fwd to making it.
THanks for the great recipes!!
I live In USA and would cook vegetable beef soup.
I live in the United States of America. I want to make pea soup. This recipe for French Onion soup looks so good and I think I will be making it soon.
I’m from Australia. I was originally going to try your coq au vin recipe because it looks slightly similar to your beef cheeks recipe (which is a favourite in my house), then I saw your Guinness beef recipe and would definitely make that first! I love comfort food and have been dying for a Dutch (French!) oven for years but couldn’t ever spend that much!