Name: Creamy French Onion and Mushroom Soup Recipe
Prep time: 15 min
Cook time: 45 min
Total time: 1 h
Cuisine: French
Ingredients: 6 tablespoons salted butter; 4 medium yellow onions, thinly sliced; 1 teaspoon honey; 1 cup low-sodium chicken or vegetable broth (for deglazing); 6–8 cups low-sodium chicken or vegetable broth; 1 tablespoon apple cider vinegar; 2 teaspoons Worcestershire sauce (or soy sauce); 2 bay leaves; Kosher salt and black pepper, to taste; 3 cloves garlic, minced or grated; 2 cups cremini or wild mushrooms, sliced; 2 tablespoons fresh thyme leaves; 2 tablespoons chopped fresh sage; 1/2 cup heavy cream; 6 slices French bread; 2 cups shredded Gruyère cheese

Jump to Recipe· 3.9 from 74 reviews

There is something utterly comforting about a warm bowl of soup that feels like a hug in a dish, and this Creamy French Onion and Mushroom Soup Recipe is exactly that kind of magic. Combining the rich caramelized sweetness of onions with the earthy savoriness of mushrooms, all enveloped in a luxuriously creamy broth, this soup turns humble ingredients into an unforgettable experience. Whether you’re crafting a cozy weeknight dinner or a special treat for guests, this soup brings layers of flavor and heartwarming depth that will have everyone asking for seconds.

Ingredients You’ll Need

A close-up view of thin, golden-brown caramelized onion slices mixed with small green herb leaves, cooking in a black pan. The onions have a glossy, soft texture with some slightly crispy edges, and a vintage wooden spatula is lifting a portion from the pan, showing the shiny, cooked layers of onions and herbs. The background is out of focus, emphasizing the rich colors and textures of the onions. Photo taken with an iphone --ar 4:5 --v 7

This recipe shines because of its simplicity and the quality of the ingredients, each of which plays a vital role in building the soup’s depth and heartwarming character. From the sweet caramelized onions to the fresh herbs and creamy finish, every element is essential.

Salted butter: The base fat that helps caramelize onions beautifully and adds richness.
Yellow onions: Thinly sliced for their natural sweetness that develops as they caramelize.
Low-sodium chicken or vegetable broth: Used for deglazing and forming the soup’s comforting base.
Apple cider vinegar: Adds a subtle tang to balance the sweetness of the onions.
Garlic: Minced or grated to infuse a gentle pungency and warmth.
Cremini or wild mushrooms: Provide earthy depth and texture.
Fresh thyme leaves: Herbaceous notes that enhance the rustic flavors.
Fresh sage: Adds a subtle woodsy aroma to complement mushrooms.
Honey: A touch of sweetness to help the onions caramelize evenly.
Worcestershire sauce or soy sauce: For umami richness and a touch of complexity.
Bay leaves: For subtle herbal undertones during simmering.
Kosher salt and black pepper: To season and enhance all of the layers of flavor.
Heavy cream: The creamy finish that makes this soup decadently smooth.
French bread slices: Toasted to provide a sturdy, crispy base for the cheese topping.
Gruyère cheese: Rich and melted to golden perfection atop the soup.

How to Make Creamy French Onion and Mushroom Soup Recipe

Step 1: Caramelize the onions

Start by melting the butter with the honey in a large Dutch oven over medium-high heat. Add the thinly sliced onions and cook them patiently, stirring every few minutes. This slow caramelization process brings out their natural sweetness, turning them soft and beautifully golden. To deepen the flavor, gradually add a small amount of broth, letting it evaporate as you stir. This careful attention unlocks the rich base that defines this soup’s charm.

Step 2: Add garlic, mushrooms, and herbs

When the onions have reached that perfect caramelized state, introduce the minced garlic, sliced mushrooms, fresh thyme leaves, and chopped sage. Season this fragrant mixture with kosher salt and black pepper and cook for a few minutes until the mushrooms release their moisture and the herbs become fragrant. This step infuses the soup with earthy and herbal dimensions that will make every spoonful captivating.

Step 3: Build the soup base

Next, pour in the remaining broth, apple cider vinegar, Worcestershire sauce, and bay leaves. Bring the whole pot up to a gentle simmer over medium-high heat and let it cook for about 10 minutes. This simmer melds all the components together beautifully while enhancing the complexity of flavors. Don’t forget to remove the bay leaves before moving on!

Step 4: Stir in the cream

The finishing touch to the broth is the addition of heavy cream, stirred in to create the signature creamy texture of the soup. Let this cook gently for an additional 5 to 10 minutes, allowing the soup to thicken slightly and all the flavors to meld into a silky, harmonious concoction.

Step 5: Prepare and toast the bread

While the soup simmers, preheat your oven to 400°F (200°C). Lay the French bread slices on a baking sheet and toast them until they are very dry and slightly golden. This step ensures your bread will hold up perfectly in the soup and gain a satisfying crunch under the melted cheese topping.

Step 6: Broil with cheese topping

Ladle the steaming soup into oven-safe bowls. Place a toasted bread slice on top of each, then generously sprinkle about ⅓ cup of shredded Gruyère cheese over the bread. Arrange the bowls on a baking sheet and place them under the broiler, watching closely until the cheese melts, becomes bubbly, and achieves a beautiful golden-brown crust. This glorious finish is what makes the Creamy French Onion and Mushroom Soup Recipe feel indulgently special.

How to Serve Creamy French Onion and Mushroom Soup Recipe

A black soup pot with a wooden handle sits on a folded beige cloth with blue stripes over a white marbled surface. Inside the pot, three thick layers form the dish: the bottom layer is dark brown soup, followed by a layer of soft bread pieces soaked in the soup, and the top layer is melted, golden-browned cheese with a slightly bubbly texture, garnished with small green herb leaves. A vintage spoon is placed on the cloth near the pot, and a blurred piece of bread is visible in the background. Photo taken with an iphone --ar 4:5 --v 7

Garnishes

A sprinkle of fresh thyme leaves just before serving adds a pop of fresh color and brightness to contrast the rich soup. You can also lightly dust with cracked black pepper for a little extra kick if desired.

Side Dishes

This soup shines as a star on its own, but pairing it with a crisp green salad or a light vinaigrette-dressed vegetable adds welcome freshness and balance. Soft, buttered dinner rolls or a simple cheese plate also complement this soup beautifully for a heartier meal.

Creative Ways to Present

For a charming dinner party, serve the soup in individual rustic ramekins or mini cast-iron skillets instead of traditional bowls. Layer the bread and cheese right before guests arrive and broil in the kitchen for a memorable presentation that feels cozy yet elegant.

Make Ahead and Storage

Storing Leftovers

You can store leftover soup in an airtight container in the refrigerator for up to 3 days. Keep the toasted bread and cheese separate and add just before reheating to preserve that delightful crispy topping.

Freezing

The soup base freezes well without the cream. For best results, cool the soup completely, then freeze in containers, leaving space for expansion. Add the cream when reheating after thawing overnight in the fridge for maximum creaminess.

Reheating

Reheat the soup gently on the stovetop over low to medium heat to avoid curdling the cream. Stir frequently until heated through. Add freshly toasted bread and melted cheese topping when serving for the freshest experience.

FAQs

Can I use other types of mushrooms?

Absolutely! While cremini or wild mushrooms are recommended for their depth of flavor, button mushrooms or shiitake can work beautifully too. Just ensure they are fresh and sliced evenly for consistent cooking.

Is there a vegetarian version of this recipe?

Yes, simply use vegetable broth instead of chicken broth and soy sauce instead of Worcestershire sauce to keep the rich, umami character without any animal products.

Can I make this soup gluten-free?

Definitely. Replace the French bread with gluten-free bread for toasting and check that your Worcestershire sauce or soy sauce is gluten-free. The soup itself is naturally gluten-free.

What if I don’t have Gruyère cheese?

Gruyère offers a creamy and nutty flavor ideal for this soup, but Swiss cheese, Emmental, or even mozzarella are workable substitutes. Choose one that melts well and has a mild taste.

How thick should the soup be?

The soup should be creamy but still spoonable and slightly broth-like. After stirring in the cream and simmering, it will thicken a bit but remain smooth and silky rather than heavy or stew-like.

Final Thoughts

This Creamy French Onion and Mushroom Soup Recipe is the kind of dish you’ll want to come back to again and again when you crave comfort with a gourmet touch. Its beautiful harmony of caramelized onions, earthy mushrooms, fresh herbs, and melted cheese makes every spoonful a warm celebration of flavors. So grab your ingredients, take your time with the caramelization, and get ready to enjoy one of the coziest, most delicious soups you’ve ever made.