Rich and creamy French Onion soup. Starting off with a slow cook of the onions, drawing out all their moisture and flavor, then simmered in beef stock, finally topped with a slice of toasted garlic bread and covered in melted swiss cheese. Learn how to make french onion soup like a professional.
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While I enjoy making foods from all kinds of cuisines and cultures there is just something about French cooking that I appreciate so much. Maybe it's my adoration for Julia Child and how she seems to bring food to life, or maybe it's how ingredients are cared for and, with technique, used to their full potential.
Take this soup for example. One ingredient, the onion, when cooked with proper technique and care can create a dish that is so well balanced, creamy (without using cream), and rich it will surely impress your dinner guests. If you are willing to share...
The classic french onion soup is such a simple concept, requires very few ingredients, little prep, but at the same time has a major depth of flavor. While very simple to make this soup, it does require time, patience, and attention. So pour a glass of wine, tap into your inner Julia Child and let's make some soup.
Disclaimer: This soup is super simple to make, but be warned this is not your quick weeknight after sports soup. No, this is a lazy Sunday afternoon, nothing to do, nowhere to go, have extra time in the kitchen soup. Plan for around 2.5 hours from start to finish. It will be worth every minute. Most of that time will just be spent monitoring your onions to prevent burning.
Ingredients

- 2 pounds of yellow onions, finely sliced, roughly 2 quarts
- 3 tablespoons butter
- 2 tablespoons olive oil
- 1 teaspoon salt
- ½ teaspoon sugar
- 3 tablesoons flour
- 6 cups of beef stock
- ½ cup dry white wine
- 4 slices of bread, baugette or french
- 2 tablespoon softened butter
- 2 cloves of fresh garlic
Tips and Tricks
- This soup is all about those beautiful onions, so it's important that they don't burn. Browning is a good thing but once they burn, it's all over.
- Start with the heat on the lower side when sauteeing and gradually increase. If you start too hot they will easily burn. The goal is to slowly draw out the moisture and flavor, not sear them.
- Use butter and olive oil. This combo provides a couple of advantages.
- Benefits from both flavor profiles. Butter adds the creamier texture and the oil gives it more aromatic flavors.
- Butter will start to burn at a lower smoke point where olive oil can handle a little hotter. When they are paired together the oil helps the butter not burn so quickly.
- Stir the onions often and scrape the bottom of the pan to incorporate those beautiful brown bits that get stuck. That gives the soup so much flavor.
- Use a large, heavy-bottom dutch oven, braiser, pot or pan. At least 10"
- Try to avoid using a pot that has a small cooking surface. We want our onions to cook as evenly as possible. Use a wide bottom pot, braiser, dutch oven or large pan to achieve the perfect cook.
- Use a heavy bottom pot or pan like a dutch oven. The heat will be distributed more evenly. I like using a large enamel-coated braiser. Avoid a thick nonstick pan.
- Make sure your stock is warmed up before adding to the pan. When a cold liquid is added to an already hot pan it can create a lot of steam and will lose some of the flavors we just spent so long developing. Have an extra pot with your stock and bring it up to temp right before adding.
- Use a dry white wine. I am not a wine expert by any means, but because you use very little amount select a white wine you wouldn't mind drinking as well. More tips on picking the right wine.
- Bread: The best bread to use would be a baguette or french bread. Since I have an abundance of sourdough that is our preferred loaf and works just as great. Whichever you choose make sure it's sliced about ½" thick.
- Use fresh cheese. Pre-grated cheese has a coating on it that prevents it from melting as well. Make sure to use freshly grated swiss cheese as your topping.
- Serve in an oven-safe soup bowl.
Equipment Needed
A large, heavy-bottom dutch oven, braiser, pot or pan. At least 10". I prefer to use the braiser because the smaller walls make it easier to turn the onions.
Le Creuset Enamled Braiser Signature Cast Iron Shallow Casserole 3.5 Qt
Oven-safe soup bowls. There are so many fun French onion soup bowls out there but any smaller soup bowl that is oven safe works great.
Wooden Spoon
How to make French Onion Soup
Slicing Onions

Start off but slicing your onions as thin as possible.
Cut the onion through the center, starting at the root but keeping it intact, and peel.
Lay onions on the flat side and give one slice down the middle. This will make it so the onions are not too long.
Then carefully slice from the flat end down to the root and thin and even as possible.
Making the Soup
Heat your braiser or dutch oven over medium-low heat. Add in butter to melt followed by olive oil.

Add in onions and mix to coat in the butter and oil mixture.

Allow to simmer for 10 minutes to draw out the moisture and soften a bit.
Mix in salt and sugar.

Sautee for 30-40 minutes stirring often so the onions don't get stuck or burn to the bottom of the pan. Scrape off any brown bits and incorporate them back into the onions.

Keep going until the onions start to turn a golden brown color. Keep a close eye on the heat and adjust if the onions are cooking too quickly or start to burn at all.

While the onions are cooking bring the beef stock to a boil in a separate pan.
Once onions are fully cooked add in the flour and mix well. Cook for about 3 minutes or until the flour is fully incorporated and cooked. We don't want raw pieces of flour or it will get clumpy once the stock is added.

Slowly add the hot beef stock to the onions. Scrape the pan as needed.
Taste and add more salt if needed.
Pour in the wine and bring the mix to a gentle simmer.

Simmer for 45-50 minutes or until the liquid has reduced, wine is cooked out, and starts to thicken.
Now you can be done here and be proud of what you have made. Grab a toasted piece of sourdough or french bread and plummet into this beautiful soup.

However, if you move on to the next two steps I promise you, it's worth it. That first complete bite of soaked bread, creamy soup, and melted cheese will be the icing on the cake.
Prepare Bread
Right before the soup is ready to serve the bread will need to be toasted. This is because during the final baking it will be sandwiched between a soup and melting cheese so the bread itself will not have the space to cook. Toasting ahead of time also makes it less spongy and will hold up better sitting in the soup. This is a simple step that brings the entire dish to the next level.
First, preheat the oven to 350 degrees.
On an oven-safe rack place your bread and bake for 5 min.

Take it out, flip it over, and spread softened butter to each slice. Then take a smashed piece of fresh garlic and rub each piece of bread. Transfer back to the oven and bake for another 5 minutes or until it starts to turn golden brown.
Assembling the Soup
Place four oven-safe bowls on a cookie sheet lined with tin foil.
Divide soup among the bowls, top with a piece of bread, and sprinkle grated swiss cheese on top.

Transfer to oven (350 degrees) and bake for 20 min. Once the cheese is melted and starting to bubble switch the oven to the broil until the cheese starts to get brown spots.
Remove from oven and allow to cool for 5-10 minutes.
Serve hot.


I would love to hear if you made this recipe! Share in a comment below or tag me on Instagram.
Learn how to grow your very own onions in the garden this spring!
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French Onion Soup
Equipment
Ingredients
Soup
- 2 Pounds Yellow Onions Finely sliced
- 3 tablespoon Butter
- 2 tablespoon Olive Oil
- ½ teaspoon Sugar
- 1 teaspoon Salt
- 3 tablespoon all purpose flour
- 6 Cups Beef Stock Can use vegetable stock as well
- ½ Cup White Wine
Bread Topping
- 4 Slices Baugette or French Bread Sliced about 1" thick. Can also use Sourdough
- 2 tablespoon Softened Butter
- 2 Garlic Cloves
- 1 Cup Freshly Grated Swiss Cheese
Instructions
Make the Soup
- Start off by finly slicing all the onions.
- Heat a braiser or dutch oven over medium-low heat.
- Melt butter and add olive oil.
- Add in onions and mix to coat.
- Simmer for 10 minutes until they start to soften a bit and release some moisture.
- Stir in salt and sugar.
- Slowly cook onions for 30-40 minutes stiring often and scraping brown bits of the pan to incorporate back into the onions. We want the onions to cook very slowly so they dont burn.
- Cook until the onions are carmalized and a deep brown color.
- While onions are cooking bring beef stock to a boil in a separate pan.
- Once onions are done add in the flour and mix well. Cook for 3 minutes or until all the flour is completely incorporated.
- Slowly add in the beef stock, scraping the pan in the proess. Taste and add salt as needed.
- Add in the white wine and bring to a gentle simmer.
- Simmer partially covered for 45-50 minutes or until the liquid reduces and starts to thicken. Stir often.
Prepare Bread
- While the soup is cooking prepare the bread.
- Preheat oven to 350 degrees.
- Prepare a baking pan with an oven safe rack.
- Place bread slices on rack and bake for 5 mintes.
- Remove from oven, flip slices, spread with butter and rub smashed pieces of garlic on each slice.
- Return to oven for another 5-10 minutes or until toasted.
Assemble Bowls
- Divide soup into 4 oven safe bowls.
- Place piece of bread on top of each soup bowl and sprinkly the grated swiss cheese.
- Return to the hot oven and bake for 15 minutes or until cheese is melted.
- Switch to broil and bake under hot elements until cheese gets nice brown spots and is bubbly.
- Remove from oven and allow to cool for 5-10 minutes.
- Serve warm and enjoy!
Video
Notes
- This soup is all about those beautiful onions, so it's important that they don't burn. Browning is a good thing but once they burn, it's all over.
- Start with the heat on the lower side when sauteeing and gradually increase. If you start too hot they will easily burn. The goal is to slowly draw out the moisture and flavor, not sear them.
- Use butter and olive oil. This combo provides a couple of advantages.
- Benefits from both flavor profiles. Butter adds the creamier texture and the oil gives it more aromatic flavors.
- Butter will start to burn at a lower smoke point where olive oil can handle a little hotter. When they are paired together the oil helps the butter not burn so quickly.
- Stir the onions often and scrape the bottom of the pan to incorporate those beautiful brown bits that get stuck. That gives the soup so much flavor.
- Use a large, heavy-bottom dutch oven, braiser, pot or pan. At least 10"
- Try to avoid using a pot that has a small cooking surface. We want our onions to cook as evenly as possible. Use a wide bottom pot, braiser, dutch oven or large pan to achieve the perfect cook.
- Use a heavy bottom pot or pan like a dutch oven. The heat will be distributed more evenly. I like using a large enamel-coated braiser. Avoid a think nonstick pan.
- Make sure your stock is warmed up before adding to the pan. When a cold liquid is added to an already hot pan it can create a lot of steam and will lose some of the flavors we just spent so long developing. Have an extra pot with your stock and bring it up to temp right before adding.
- Use a dry white wine. I am not a wine expert by any means, but because you use very little amount select a white wine you wouldn't mind drinking as well. More tips on picking the right wine.
- Bread: The best bread to use would be a baguette or french bread. Since I have an abundance of sourdough that is our preferred loaf and works just as great. Whichever you choose make sure it's sliced about 1" thick.
- Use fresh cheese. Pre-grated cheese has a coating on it that prevents it from melting as well. Make sure to use freshly grated swiss cheese as your topping.
- Serve in an oven-safe soup bowl.
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