Bistro French Onion Soup

This Bistro French Onion Soup Recipe is completely homemade and perfect for a chilly day! Caramelized onions, melty cheese, and crusty bread make this one of the best soups ever. It’s easy enough for a novice and delicious for everyone in the family.

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Now that the weather has cooled off, it’s definitely soup season! One of my favorite soups is this Bistro French Onion Soup, probably because there is a lot of melty cheese involved. Not only will you have a warm and delicious soup to serve, but your house will also smell amazing when the onions are caramelizing!

Ingredients needed for Bistro French Onion Soup

• 4 large yellow onions, sliced into crescents
• 3 tablespoon unsalted butter
• 2 tablespoons olive oil
• 1 teaspoon salt
• freshly ground black pepper
• 1 tbsp sugar
• 3 tablespoons all-purpose flour (skip if you want a gluten-free option)
• 6 cups broth (beef, chicken, or vegetable)
• 1/2 cup white wine (optional)
• 1 handful of fresh oregano or any fresh herb you like
• 1 crusty baguette sliced or cubed
• 2-3 cups gruyere cheese, shredded
• fresh parsley for garnish if desired

How to make This Super Easy French Onion Soup

1. For this recipe, I used a dutch oven to cook the onions and soup in. The heat of the cast iron helps with the onion caramelization. Add the butter and oil and melt over medium-low heat. After the butter stops bubbling, add the onions and stir to coat the onions. Cover and cook for 15 minutes on low.
2. Remove the lid and add salt, pepper, and sugar to get the caramelization going. Continue to cook on medium-low heat for 25-30 minutes, stirring often, until the onions are nice and brown.
3. Add the flour to the onions and stir for about 60 seconds. Add the broth, wine, and herbs to the onions, and cook partially covered on low heat for about 40-45 minutes. While the soup is cooking, slice the bread into slices or large cubes and brown under a broiler for a few minutes to get them crispy.
4. Pour the soup into individual serving bowls that are oven-safe. Top with the bread slices or cubes and then a generous amount of cheese. Place the bowls under the broiler in the oven until the cheese is melted and bubbly. Remove from oven and allow to cool for a few minutes before serving. Enjoy, and remember, it’s VERY hot!!!

How Many Carbs in French Onion Soup?

My version of french onion soup has 51.3g of carbs per serving. Most of this is from the crusty baguette on top. So if you are watching your carbs, omit the bread.

You can make this soup gluten-free or skip the wine

This recipe is pretty simple and there are so many ways to adjust it to your liking. If you are gluten-free, leave out the flour. You can also use whatever fresh herbs you have on hand. The wine is also optional but highly recommended. Ok, the wine is recommended for taste and also because you will have a full bottle of wine that has to go somewhere… Did I mention this soup is delicious with wine?? 😂 🍷

What type of onions to use for Bistro French Onion Soup

I usually use basic yellow or white onions for French Onion Soup, but you can use any onion you like. Yellow and white onions create a nice sweetness and tend to be the least expensive. You can usually find either of these in bulk bags which makes it even more convenient and cost-efficient. Red onions will work as well but tend to be a little more bitter and sweet onions are delicious but tend to be a little more expensive.

How do I get melted cheese on top of soup?

Gruyere cheese is the most common cheese used for french onion soup. I highly recommend it not only for its melty quality but for the nutty and salty flavors you get from Gruyere. However, if you do not have or like Gruyere, you can also use mozzarella or Monterey cheese since they both melt well. Most grocery stores have cheese experts in the cheese section and they could guide you as well.

You will also need oven-safe bowls to melt the cheese on top. I usually used my Fiesta bowls or an oven-safe stoneware bowl, they never fail me. After you have cooked the soup, add some bread to the top and then a generous amount of cheese. Place the oven-safe bowl under the broiler in the oven for a few minutes until the cheese has melted and is nice and bubbly.

More Easy and Delicious Dinner Recipes:

• Chile Relleno Enchiladas
• Gluten-Free Chicken Broccoli Bake
• Perfect Dry Brined Turkey
• Air Fryer Chicken Nuggets
• Instant Pot Korean Burritos

Bistro French Onion Soup

This easy homemade Bistro French Onion Soup Recipe is perfect for a chilly day! Caramelized onions, melty cheese, and crusty bread make this one of the best soups ever. It's easy enough for a novice and delicious for everyone in the family.

5 from 12 votes

Print Pin Rate

Prep Time: 10 minutes

Cook Time: 1 hour 30 minutes

Total Time: 1 hour 40 minutes

Servings: 6 servings

Calories: 531kcal

Author: EmilyFabulous

Equipment

• dutch oven or large pot
• oven-safe serving bowls

Ingredients

• 4 large yellow onions, sliced into crescents
• 3 tablespoons unsalted butter
• 2 tablespoons extra virgin olive oil
• 1 teaspoon kosher salt
• ½ teaspoon freshly ground black pepper
• 1 tablespoon sugar
• 3 tablespoons all-purpose flour (skip if you want a gluten-free option)
• 6 cups broth (beef, chicken, vegetable)
• ½ cup white wine (optional, you can sub more broth)
• ½ tablespoon fresh thyme (can sub fresh rosemary)
• ½ tablespoon fresh sage
• 1 crusty baguette sliced or cubed
• 2-3 cups gruyere cheese, shredded

Instructions

• In a large pot, add the butter and olive oil and melt over medium heat. After the butter stops bubbling, add the onions and stir to coat them. Cover the pot with a lid and cook for 15 minutes on med-low heat.
  
• Remove lid and add salt, pepper, and sugar to get the caramelization going. Continue to cook on medium-low heat for 25-30 minutes, stirring often, until the onions are nice and brown. Keep an eye on the heat level because you don't want them to stick and burn at the bottom.
  
• Add flour to onions and stir for 60 seconds, then add the broth, wine, and herbs and cook partially covered on low heat for 40-45 minutes. Add salt and pepper to taste if needed.
  
• While the soup is cooking, slice the bread into slices or large cubes and brown under the broiler for a few minutes to get them brown and crunchy. This only takes about 2-3 minutes per side.
  
• Pour the soup into individual serving bowls that are oven safe. Top with bread slices or cubes and then a generous amount of cheese. Place the bowls under the broiler in the oven until the cheese is melted and bubbly.
  
• Remove the bowls from the oven and allow the soup to cool for a few minutes before serving. Enjoy, and remember, it's VERY hot!!!
  

Nutrition

Serving: 1serving | Calories: 531kcal | Carbohydrates: 51.3g | Protein: 24.2g | Fat: 24.7g | Saturated Fat: 12.3g | Cholesterol: 55mg | Sodium: 1663mg | Potassium: 411mg | Fiber: 3.5g | Sugar: 9.2g | Calcium: 447mg | Iron: 3mg

Any nutrition calculations are only estimates using online calculators. Please verify using your own data.

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