French Onion Soup is one of the most delicious soups that most people enjoy only when they’re dining out in a restaurant. Today I’m going to show you how to make one of my favorite Best Fall Soup Recipes that’s topped with homemade croutons and tons of cheese!

Easy French Onion Soup with Mozzarella Cheese and Homemade Croutons
This recipe has been updated since it first appeared in 2014 with new photos and a new printable recipe card that includes nutritional information. I hope you enjoy the updates as much as I enjoyed working on them!
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French Onion Soup
French Onion Soup is one of my favorite soup recipes! My husband and I love ordering French Onion Soup when we go out to dinner.
You might think this soup is difficult to make, but after you see the video below, you’ll agree it’s a recipe anyone can make right at home in their own kitchen.
This recipe is not only great for dinner, but any leftovers freeze beautifully. On busy days, I take a container of this soup out of the freezer to enjoy for dinner.
Tips for Making Homemade French Onion Soup
- Traditional French Onion Soup recipes use Gruyere cheese or provolone cheese.
- I’m using mozzarella cheese for French Onion Soup.
- Another way to make this recipe is easy is by using homemade croutons instead of a single thick slice of French bread. It’s so much easier to enjoy the soup without having to try breaking the thick sliced bread into pieces. Or am I the only one that has problems doing that?
- You’ll notice that there is no alcohol added to this recipe.
Ingredients:
Make sure you print out the recipe below and save it for later!
- Thinly sliced yellow onions- you need about 5 cups of onions, so I suggest using a food processor, but a sharp knife works great too!
- Butter
- Bay Leaf
- Beef Broth
- Flour
- Sugar – I’ve had a few people email me asking why you need to add sugar to the onions and not only does it add flavor, but it helps caramelize the onions to get that deep rich color.
- Salt and pepper – this is for the homemade croutons. The beef broth should have enough salt. However, taste the soup after it has cooked and add more if you need to.
- Loaf of French bread to make homemade croutons
- Mozzarella cheese
- Parmesan cheese
Directions:
In a large stock pot, melt the butter and add the sliced onions. After a few minutes of cooking, add the sugar and continue to cook the onions slowly, stirring frequently, for about 30 minutes; until they turn a deep golden brown. Next, add the flour and cook for another few minutes.

How to Brown and Caramelize Onions for Homemade French Onion Soup.
This is the color the onions should be after they have cooked for about 30 minutes. They are a beautiful deep golden brown.
Now, add the beef broth and bay leaf. Allow the French onion soup to simmer for another 30 minutes. Taste the soup and see if it needs any salt or pepper. I always wait till the end to season as the broth can add enough saltiness.
Easy French Onion Soup Recipe with Croutons
Traditionally, you add a thick slice of French bread. Then it’s topped with cheese and placed under the broiler until the bread and cheese are melted. I find it easier to enjoy the soup by adding homemade croutons instead of a thick slice of bread.
How to Make Homemade Croutons:
- Slice the French bread into cubes.
- Butter each cube as you place them on a baking sheet lined with either aluminum foil or parchment baking sheets.
- Sprinkle with salt and butter.
- Place the baking tray under the broiler for a few minutes until the homemade croutons are golden brown.
How to Serve the Soup:
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Spoon the soup into an oven-safe bowl and top with the homemade croutons.
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Top with the homemade croutons.
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Then add about 2 tablespoons of mozzarella cheese on top of the croutons.
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Place the bowls of soup under the broiler for a few minutes or until the cheese is melted.
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Sprinkle Parmesan cheese on top before serving.

How to make Homemade Croutons.
Helpful Kitchen Tools:
- Mandolin slicer – this tool will get your onions really, really thin. Just make sure you use the safety guard!
- Stainless Steel Cheese Grater
- Oven-proof soup bowls
- Dutch Oven Stock Pot – I love to cook with cast iron.
You Might also Enjoy these Soup Recipes:
- Homemade Potato Corn Chowder
- Italian Tomato Soup – with grilled cheese croutons!
- Homemade Potato Soup

French Onion Soup
French Onion Soup is one of the most delicious soups that most people enjoy only when they’re dining out in a restaurant. Today I’m going to show you how to make this easy recipe that’s topped with homemade croutons and tons of cheese!
Ingredients
- 5 cups of thinly sliced yellow onions
- 4 tbsp butter
- 1 bay leaf
- 8 cups beef broth
- 3 tbsp flour
- 1 tsp sugar
- Salt and pepper - to taste
- 1 small loaf of French Bread cut into cubes
- 1/4 cup softened butter
- 2 cups Mozzarella cheese
- 1/4 cup Parmesan cheese
Instructions
How to Prepare the Soup
- In a large stock pot, melt the butter and add the sliced onions.
- After a few minutes of cooking, add the sugar and continue to cook the onions slowly, stirring frequently, for about 30 minutes; until they turn a deep golden brown.
- Add the flour and cook for another few minutes.
- Then add the beef broth, bay leaf and allow the soup to simmer for another 30 minutes.
- Taste the soup and see if it needs any salt or pepper. I always wait till the end to season as the broth can add enough saltiness.
- Remove the bay leaf and keep the soup warm while you prepare the homemade croutons.
How to Prepare the Homemade Croutons
- Cut the French bread into cubes and spread the softened butter on top. Sprinkle with salt and pepper if desired.
- Place them on a parchment lined baking sheet and toast them in a preheated 425 degree oven for about 5 to 8 minutes or until they are golden browned.
How to Put the Soup Together
- Spoon the soup into an oven-safe bowl and top with the homemade croutons.
- Then sprinkle about 1/4 to 1/3 cup of mozzarella cheese to the top of each bowl.
- Place the bowls of soup under the broiler for a few minutes or until the cheese is melted.
- Sprinkle freshly grated Parmesan cheese on top before serving.
Notes
Traditionally, Gruyere cheese is used for French Onion Soup. I have used Swiss cheese, Mozzarella cheese and Provolone cheese. Any flavor of cheese really works with this recipe, so choose your favorite!
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Nutrition Information:
Yield: 6 Serving Size: 1Amount Per Serving: Calories: 416Total Fat: 26gSaturated Fat: 16gTrans Fat: 1gUnsaturated Fat: 8gCholesterol: 74mgSodium: 1741mgCarbohydrates: 30gFiber: 3gSugar: 10gProtein: 17g
The nutrition information is calculated automatically. I cannot guarantee its accuracy. If this data is important to you, please verify with your trusted nutrition calculator.
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So happy to hear this turned out so great for you! And thank you for sharing with us! 🙂
I love French onion soup. I am going to try this recipe this weekend. I love the idea of using homemade croutons, it will make it easier to eat. I’m very excited about this.
Hope the soup turned out great for you! Thanks for visiting.
This sounds wonderful and so simple. I was surprised. But could you please review the last few steps? I see nothing about adding the cheese but two bits about adding croutons. Thanks for sharing!
Thank you Teddee. I fixed the recipe card to show that you add the cheese on top of the croutons before placing the bowls of soup in the oven.
Yum! French Onion is my absolute favorite soup. Thanks for sharing with us at the Waste Not Wednesday Link Party. Looking forward to seeing what you are up to this week.
How nutritional the soup is! Thanks for sharing this recipe.
Its just lovely my dear.
This was an easy & delicious recipe to make.Homemade croutons too. I didn't even have any left to freeze, just enough to make another bowl.
I LOVE French Onion soup! and I really like that you use cubed bread instead of a slice. Makes it so much easier to eat.
That looks delicious!! I always want to make this, but can never find the time. Pinned it to try! #HomeMattersParty
I adore French Onion Soup. It is easy to make but somehow seems like it should be harder. Congrats on your feature on the #HomeMattersParty
Hey, Lois! Just wanted to let you know that we loved your French Onion Soup so much when you shared it at the #HomeMattersParty last week, we’ve FEATURED it THIS WEEK! Hope you can check it out when you get a sec! Happy Friday!!! http://lifewithlorelai.com/2015/10/08/home-matters-linky-party-58/
~Lorelai
Life With Lorelai / Home Matters Linky Party
We just love French Onion Soup. I haven't made this in a while but I think it's time this week now that the weather is cooling down. Thanks so much for sharing with Foodie Friends Friday party this weekend. Pinning/sharing.
Sounds delicious – thanks for the recipe! Pinned to share and definitely making this soup soon.
Oh my-I just LOVE French Onion Soup! Can't wait to try your recipe!!! Pinning and sharing! Thank you for linking up to The Wonderful Wednesday Blog Hop!
Yum- I LOVE french onion soup. Can't wait to try this!
I stopped by from Inspire Me Monday!
I love French Onion.Thank you for such a easy recipe.
I'd love a bowl of this!! Thanks for linking up with SNF! Pinned to our party board!!
This recipe is amazing! I'm so glad you shared it at last week's Project Stash Link Party. We featured you and pinned you onto our Pinterest board! The party opens at 8:00 pm tonight so stop by, grab a featured button, and share how you've used your stash this week! 🙂 http://goo.gl/kOb80u
We love French onion soup – I am definitely going to be trying this. Thank you for sharing at Share It One More Time. Cathy
My husband and I LOVE French Onion Soup, but we are picky with flavor. Can you tell me why you add sugar? Just curious as I can't recall seeing anyone else use sugar in this recipe. Sounds yummy though and the picture makes me crave all over again.
Hilary, it just takes the "bite" out of the onion. And it's not much. You could probably leave it out! I hope you try the recipe. Thanks so much for visiting!
I am printing it out now. Any tips on how to keep the house from wreaking of onions? lol
Well, I've found that a nice scented candle helps. 😉 There is a smell when you're cooking that many onions! Thanks Hillary!
I love French Onion Soup and I've never prepared it myself. This looks so easy. Pinned to try!
What a great recipe! I'm definitely going to try it. Thanks for sharing. Pinning it!
This looks delicious! I love French onion soup. Thank you for the recipe. 🙂 Pinned.
Kelly
http://www.alovelylifeindeed.com
Thanks for stopping by and for pinning Kelly!
Yummy.. My husband loves French Onion Soup!
Mine too Lynn! Which is why I love how easy this recipe is!
Sounds great Ali!
I could sub gluten free flour and croutons! Putting on the menu for this week. One of my all time favorites!
Sounds great. Thanks for visiting Ali!