Okay, YUMMMM. Aren't soups just the best? They're a firm favourite in our house and this sweet caramelised Rustic French Onion Soup with toasty sourdough bread and melty cheese on top is both cosy and delicious, and ready to keep you warm throughout the cooler months ahead. Made with just 5 basic pantry ingredients, plus flaky sea salt and cracked pepper for seasoning, this simple soup is sugar free and jam packed with a deeply rich, slightly sweet yet satisfying flavour that will want you coming back for more, and more, and most definitely more. My secret ingredient? A really good drop of white wine to deglaze and amaze.
There is something very special about taking the time to cook the onions in a French Onion Soup; the flavour and aroma of the slow-cooked caramelised onions is truly special. The best French Onion Soups are not rushed, and either is this one. But don't be fooled by the time it takes to caramelise the onions because it's actually very simple to do. All you need is a lot of onions, a generous knob of butter, and a wooden spoon to stir the onions around occasionally in a large pot. In this case, the browner the better. When the onions are caramelised, you deglaze with a splash of good white wine, add a bit of water, bring to the boil and simmer until it's reduced a little more. Et voila! Perhaps the piècede résistance is a thick slice of sourdough bread which has been covered in gruyere cheese (or a simple mozzarella for an equally maximum cheesy pull and depth of flavour) and broiled under the grill until the cheese is bubbling away. Use this to lavishly dip into the rustic French Onion Soup for adding even more flavour.
Why you are going to love this soup?
A history lesson
For hundreds of years, French Onion Soup was seen as food for poor people because onions were plentiful and easy to grow. In it's time, it has also been touted as a hangover cure (I cannot attest to this, yet). However the more modern version datesback as far as the 18th century, in Paris when it was made from beef broth and caramelised onions. It went mainstream in the United States in the late 1860's thanks to New York restauranteur Henri Mouquin and chef wide Marie Julie Grandjean Mouquin. And as they say, the rest is history.
How to cut onions, without crying
You’ll need to cut a fair few onions in this recipe and I don’t want there to be any tears. I’ve been sitting here trying to think about how I can explain to you how to cut onions without crying. Instead I found this video on YouTube. Watch till 1 minute 44 seconds and then cut the top of the onion off so you’re left with a beautifully sliced onion. And no tears.
One last note
Please do try this insanely delicious recipe – it really is so simple and so flavourful! If I have inspired you to make this Rustic French Onion Soup, and if you love my recipe (fingers crossed), I would love you to leave a 5 star rating below. And did you know? You can also stay in touch with me by following along on Instagram and Pinterest.
14 brown onions, peeled and sliced finely
Large knob of salted butter
2 tsp flaky sea salt and 1 tsp cracked pepper
1 1/2 cup white wine
5 cups of water
1 slice of sourdough bread, per person
Gruyere or mozzarella cheese, grated
Fresh sprig of rosemary
In a large pot on medium heat, butter and onions. Brown the onions until they are reduced by half, dark brown in colour and caramelised. Delicious umami tasting caramelised onion paste will stick to the sides of the pot as the onions reduce, so scrape down the sides occasionally and mix back into the onion mixture for maximum flavour. Cook the onions down for 1 hour. You may need to add a splash of water towards the end once or twice. Season with salt and pepper.
When the onions are dark brown and caramelised (go on, have a taste - they will be DELICIOUS), deglaze the pot with white wine. Stir, add water and bring the heat up to high. Stir again and bring to boil.
When the soup is boiling, turn the heat down to medium and let it simmer and bubble away uncovered for at least 20 minutes.
It's time to get your cheesy toast ready. Turn the grill of your oven on and line a baking tray with aluminium foil. Sprinkle a generous mount of cheese all over one side of the bread and grill until the cheese is bubbling away and golden in colour on top. Take the cheese toast out of the oven. Sprinke with fresh rosemary sprigs. And serve.
Alternative: Pour your French onion soup into an oven proof dish, I used my Solid Teknics AUS-ION "Raw" 21cm Wrought Iron Deep Pot. Place your slices of cheese toast on top and sprinkle extra cheese in one corner on top of the French Onion Soup. Grill until the cheese in the soup has melted. Sprinkle with fresh rosemary sprigs. And serve.