Deliciously tasty, this gluten-free French onion soup recipe is full of caramelized onions in a rich broth brimming with flavor. Topped with gluten-free croutons and dairy-free cheese, this onion soup is the perfect appetizer or light meal for warming up to during the winter! Totally dairy-free too.
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Jump to:
- It’s Soup Season. Cozy Up to a Bowl of Soup!
- Our Favorite Soup Recipes:
- What is French Onion Soup?
- Why This Recipe Works:
- Ingredients You’ll Need
- Recipe Notes + Substitutions
- How to Make Gluten-Free French Onion Soup (Step by Step):
- Dish by Dish Tips/Tricks
- Recipe FAQs:
- Other Gluten Free Soup Recipes to Enjoy:
- Gluten-Free French Onion Soup (Dairy-Free)
It’s Soup Season. Cozy Up to a Bowl of Soup!
The weather is definitely getting colder now that we’re in the midst of winter, and as I always say, a big bowl of soup is the perfect antidote and comfort food for the cold!
Comforting, cozy and warm, there’s nothing a big bowl of soup cannot make better!
What is French Onion Soup?
Apparently it seems that onion soup has long been popular since Roman times, thanks to how accessible onions were.
Then, the version of traditional French onion soup as we know it today actually originated in the 18th century in Paris, France, where the main ingredients for the classic recipe were caramelized onions and beef broth.
If you’ve never tried French onion soup before, you’re in for a glorious surprise!
Made with meat broth and plenty of tasty caramelized onions, the soup is usually served with croutons or a slice of bread with gratinated cheese on top.
Why This Recipe Works:
- Simple Ingredients: The main ingredients required for this gluten-free French onion soup recipe are easily accessible at the local grocery store (you probably already have most on hand).
- Easy to Make: While it does involve quite a bit of active hands-on time, this gluten-free onion soup recipe is not complicated at all, so don’t worry even if it;s your first time making it!
- Totally Gluten-Free and Dairy-Free: The best part is that this flavorful French onion soup recipe is 100% gluten-free and dairy-free, which means that even those with Celiac disease or gluten or lactose intolerances can enjoy it without issues!
Ingredients You’ll Need
Here’s a visual overview of the ingredients required for this gluten-free French onion soup recipe.
(For exact measurements and quantities, please scroll down to the recipe card at the bottom of this post.)
Recipe Notes + Substitutions
- White Wine Vinegar: I used white wine vinegar, but you can also use apple cider vinegar if you prefer.
- Sugar: I used white sugar, but feel free to use light brown sugar, dark brown sugar or coconut sugar. Alternatively, if you are diabetic or insulin-resistant, I highly recommend using granulated monkfruit sweetener (a 1:1 sugar substitute that is zero glycemic index and will not raise your blood sugar).
- Tomato Sauce: You can use a store-bought or homemade tomato sauce. Alternatively, you may also use tomato ketchup if you prefer.
- Olive Oil: I like using extra virgin olive oil for its flavor, but you may also use another vegetable oil (such as sunflower oil, corn oil, avocado oil). You can also use melted vegan butter. Alternatively if you are not lactose-intolerant, feel free to use melted butter or ghee instead.
- Onions: I used yellow onions, but you can also use white onions or red onions (or a mix of all three!). Sliced onions are most commonly used in French onion soup, but you may also use diced onions.
- Gluten-Free All-Purpose Flour: I used gluten-free all-purpose flour to keep this recipe gluten-free. You can also use tapioca starch or arrowroot starch instead. However, if you are not Celiac or gluten-intolerant, feel free to use normal flour instead.
- Beef Broth: Traditionally, beef broth is used in making authentic French onion soup, but you may also use beef stock or chicken stock if you prefer. If you wish to keep this recipe vegetarian, feel free to use vegetable broth or stock instead. If you are Celiac or gluten-intolerant, make sure to use gluten-free beef broth.
- Tamari: I used tamari (a gluten-free version of soy sauce) to keep this recipe gluten-free. You may also use coconut aminos if you prefer.
- Cornstarch: Cornstarch is used as a thickener to thicken the soup, but you may also use tapioca starch or arrowroot starch in equal quantities if you prefer.
- Thyme: Adding dried thyme adds a beautiful flavor to this bistro French onion soup. Alternatively you may use fresh thyme sprigs, but only add the fresh herbs towards the end of the cooking process. Feel free to add bay leaves too if you wish.
- Garlic Powder: I love adding garlic powder because it adds plenty of flavor. Alternatively, you can use granulated garlic instead.
- Onion Powder: Adding onion powder also contributes to the sweet onion flavor in this soup. Alternatively, you can use granulated onion instead.
- Black Pepper: A sprinkle of ground black pepper adds a slight kick of heat, but feel free to leave it out if you aren’t a fan of pepper.
- Croutons: I used gluten-free croutons to keep this recipe gluten-free, but you may also use gluten-free bread slices instead. Alternatively, if you are not Celiac or gluten-intolerant, you may use normal croutons instead.
- Mozzarella Cheese: I used dairy-free mozzarella cheese to keep this recipe dairy-free, but if you are not lactose-intolerant, you may use normal mozzarella cheese instead.
How to Make Gluten-Free French Onion Soup (Step by Step):
1. Prepare Tomato Gastrique
Start by creating the tomato gastrique by boiling the white vinegar in a saucepan or skillet until it has boiled down to half its amount of liquid. Add the sugar to the white vinegar and mix continuously for about 3-5 minutes or until the mixture has become syrupy. Add the tomato sauce to this syrup and mix until combined. Then remove the tomato gastrique from the heat.
2. Sauté Onions Until Caramelized
In another large saucepan heat up the olive oil and sauté the sliced onions on medium heat for about 20 minutes, or until the onions have become golden brown and are caramelized.
3. Add Flour to Caramelized Onions
Add the flour and mix the onions until they are fully coated and the flour-covered onions soak up all the juices.
4. Combine Ingredients in Pot
Transfer the flour-coated onions to a large pot or Dutch oven and add in the beef broth, tomato gastrique (from Step 1), soy sauce, cornstarch and all the seasonings. Stir this mixture together.
5. Simmer Over Low Heat
Simmer the soup over low heat for 15-20 minutes, stirring every so often.
6. Garnish with Croutons, Cheese and Serve
When serving in a bowl, top with croutons and cheese, if available use a butane torch to melt the cheese and enjoy!
Alternatively (if you don’t have a butane torch), serve this gluten-free onion soup in oven-proof bowls, top with crusty bread or croutons and cheese, and broil until cheese is gratinated or melted.
Dish by Dish Tips/Tricks
- Make Ahead: If making the soup beforehand, do not add the croutons or mozzarella until you are ready to eat or serve the onion soup. Place the soup in an airtight container and store in the refrigerator for up to 4 days. Reheat the soup in a pot or the microwave before adding croutons and cheese on top of the soup.
- Use a Slow Cooker: If you wish, once the onions have been caramelized, combine all the ingredients (except the croutons and cheese) in a slow cooker and cook on high for 4 hours or low for 8 hours.
- Make Your Own Croutons: Homemade gluten-free croutons are actually way easier to make than you’d think! Learn how to make your own croutons today!
Recipe FAQs:
Typically, French onion soup is topped with croutons or bread made from wheat flour (which contains gluten). This means that unless specifically made to be gluten-free, French onion soup usually contains gluten. However, in this case, we’re using gluten-free croutons as well as gluten-free beef broth, so even Celiacs or those with gluten intolerances can enjoy this delicious gluten-free onion soup!
Yellow onions are usually the best candidate for making onion soup. However, if you don’t have yellow onions on hand, you can also use white onions or red onions instead.
Yes, you can freezer this onion soup (without the croutons and cheese). Simply place the soup into individual portions in freezer-safe bags and seal before freezing for up to 2 months. Thaw individual portions as and when you wish to enjoy the soup, and then place in oven-safe bowl, top with croutons and cheese, and broil until cheese is gratinated.
Other Gluten Free Soup Recipes to Enjoy:
P.S. If you try this recipe, I’d love for you to leave a star rating below, and/or a review in the comment section further down the page. I always appreciate your feedback. Be sure to check out my entire Recipe Index for all the recipes on the blog. You can also follow me on Pinterest, Facebook or Instagram! Sign up for my Email List to get fresh recipes in your inbox each week!
PrintGluten-Free French Onion Soup (Dairy-Free)
- Total Time: 1 hour
- Yield: 4 servings 1x
- Diet: Gluten Free
Description
Deliciously tasty, this gluten-free French onion soup is full of caramelized onions in a rich broth brimming with flavor. Topped with gluten-free croutons and dairy-free cheese, this onion soup is the perfect appetizer or light meal for warming up to during the winter! Totally dairy-free
Ingredients
- 1/2 cup white wine vinegar
- 1/4 cup white granulated sugar
- 1/4 cup tomato sauce
- 2 tablespoons olive oil
- 4 cups yellow onions, sliced
- 1/8 cup gluten-free all-purpose flour
- 4 cups beef broth
- 1 teaspoon tamari
- 1/2 teaspoon cornstarch
- 1 teaspoon dried thyme
- 1/2 teaspoon garlic powder
- 1/2 teaspoon onion powder
- 1/2 teaspoon salt
- 1/2 teaspoon ground black pepper
- 1 cup gluten-free croutons
- 1/2 cup dairy-free mozzarella cheese
Instructions
- Prepare Tomato Gastrique: Start by creating the tomato gastrique by boiling the white vinegar in a saucepan until it has boiled down to half its amount of liquid. Add the sugar to the white vinegar and mix continuously for about 3-5 minutes or until the mixture has become syrupy. Add the tomato sauce to this syrup and mix until combined. Then remove from the heat.
- Sauté Onions Until Caramelized: In another saucepan heat up the olive oil and sauté the sliced onions on medium heat for about 20 minutes, or until the onions have become golden brown and are caramelized.
- Add Flour to Caramelized Onions: Add the flour and mix the onions until they are fully coated and the flour covered onions soak up all the juices.
- Combine Ingredients in Pot: Transfer the onions to a large pot and add in the beef broth, tomato gastrique, soy sauce, cornstarch and all the seasonings. Stir this mixture together.
- Simmer on Low Heat: Simmer for 15-20 minutes, stirring every so often.
- Garnish with Croutons, Cheese and Serve: When serving in a bowl, top with croutons and cheese, if available use a butane torch to melt the cheese and enjoy! Alternatively, serve the soup in an oven-safe bowl and broil until cheese is gratinated or melted.
Notes
White Wine Vinegar: I used white wine vinegar, but you can also use apple cider vinegar if you prefer.
Sugar: I used white sugar, but feel free to use light brown sugar, dark brown sugar or coconut sugar. Alternatively, if you are diabetic or insulin-resistant, I highly recommend using granulated monkfruit sweetener (a 1:1 sugar substitute that is zero glycemic index and will not raise your blood sugar).
Tomato Sauce: You can use a storebought or homemade tomato sauce. Alternatively, you may also use tomato ketchup if you prefer.
Olive Oil: I like using extra virgin olive oil for its flavor, but you may also use another vegetable oil (such as sunflower oil, corn oil, avocado oil). You can also use melted vegan butter. Alternatively if you are not lactose-intolerant, feel free to use melted butter or ghee instead.
Onions: I used yellow onions, but you can also use white onions or red onions (or a mix of all three!). Sliced onions are most commonly used in French onion soup, but you may also use diced onions.
Gluten-Free All-Purpose Flour: I used gluten-free all-purpose flour to keep this recipe gluten-free. You can also use tapioca starch or arrowroot starch instead. However, if you are not Celiac or gluten-intolerant, feel free to use normal flour instead.
Beef Broth: Traditionally, beef broth is used in making French onion soup, but you may also use beef stock or chicken stock if you prefer. If you wish to keep this recipe vegetarian, feel free to use vegetable stock instead. If you are Celiac or gluten-intolerant, make sure to use gluten-free beef broth.
Tamari: I used tamari (a gluten-free version of soy sauce) to keep this recipe gluten-free. You may also use coconut aminos if you prefer.
Cornstarch: Cornstarch is used as a thickener to thicken the soup, but you may also use tapioca starch or arrowroot starch if you prefer.
Thyme: Adding dried thyme adds a beautiful flavor to the French onion soup. Alternatively you may use fresh thyme, but only add the fresh herbs towards the end of the cooking process.
Garlic Powder: I love adding garlic powder because it adds plenty of flavor. Alternatively, you can use granulated garlic instead.
Onion Powder: Adding onion powder also contributes to the onion flavor in this soup. Alternatively, you can use granulated onion instead.
Black Pepper: A sprinkle of ground black pepper adds a slight kick of heat, but feel free to leave it out if you aren’t a fan of pepper.
Croutons: I used gluten-free croutons to keep this recipe gluten-free, but if you are not Celiac or gluten-intolerant, you may use normal croutons instead.
Mozzarella Cheese: I used dairy-free mozzarella cheese to keep this recipe dairy-free, but if you are not lactose-intolerant, you may use normal mozzarella cheese instead.
Make Ahead: If making the soup beforehand, do not add the croutons or mozzarella until you are ready to eat or serve the onion soup. Place the soup in an airtight container and store in the refrigerator for up to 4 days. Reheat the soup in a pot or the microwave before topping with croutons and cheese.
- Prep Time: 10 mins
- Cook Time: 50 mins
- Category: Soups
- Method: Stovetop
- Cuisine: French
Denisemeyer says
You are the Best. I love your recipes of soups. I will to make them, isn’t tomato soup. I don’t like it .
Felicia Lim says
Hi Denise! Glad you enjoy the soup recipes 🙂
Isabelle says
Amazing French onion soup full of flavours! 10/10. Will definitely be trying your other recipes.
Thank you very much for sharing! 🙂
Felicia Lim says
So happy to hear that Isabelle! Glad to have you here!
Grace Lim says
Dear Felicia,
We currently in SG are experiencing pretty cool weather (sometimes down to 24 degrees centigrade) and a bowl of hot French onion soup is definitely a welcomed dish to warm up the body during meal time.
It had been raining quite a great deal here in SG in recent weeks and it was a good change from sunny hot tropical weather to this very cool temperature we are experiencing during the daytime ! We thank God for the cool atmosphere this CNY!
Great hugs and lots of love from SG,
Mum
Felicia Lim says
Enjoy the slightly cooler weather in SG now!! At least it’s not so hot during CNY season!