Onion Soup with Fontina

Why You’ll Love This Recipe

This version of onion soup adds a creamy, slightly nutty dimension thanks to Fontina cheese. The result is a more luxurious, melt-in-your-mouth experience compared to traditional Gruyère-based versions. It’s warm, savory, and satisfying—perfect for cold evenings or anytime you crave a bowl of comfort. Plus, it’s surprisingly easy to make with just a few humble ingredients and minimal effort.

Ingredients

(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)

yellow or sweet onions, thinly sliced
unsalted butter
olive oil
garlic, minced
dry white wine (optional)
beef broth or vegetable broth
fresh thyme (or dried thyme)
bay leaf
salt
black pepper
baguette or crusty bread, sliced and toasted
Fontina cheese, grated

Directions

1. In a large pot or Dutch oven, melt butter with olive oil over medium heat.
2. Add sliced onions and cook slowly, stirring often, for 30–40 minutes until deeply golden and caramelized.
3. Stir in the minced garlic and cook for 1 minute.
4. Deglaze the pan with white wine if using, scraping up any browned bits from the bottom. Simmer for 2–3 minutes.
5. Add beef or vegetable broth, thyme, bay leaf, salt, and pepper. Bring to a simmer and cook for another 15–20 minutes. Remove bay leaf and adjust seasoning as needed.
6. While the soup simmers, toast the bread slices until golden.
7. Preheat your broiler.
8. Ladle soup into oven-safe bowls. Top each with a slice or two of toasted bread and a generous handful of grated Fontina cheese.
9. Place bowls under the broiler until the cheese is melted and bubbly, about 2–4 minutes.
10. Serve immediately, garnished with fresh thyme if desired.

Servings and timing

This recipe serves 4 people.
Prep time: 10 minutes
Cook time: 1 hour
Total time: 1 hour 10 minutes

Variations

• Use Gruyère or Swiss cheese: If Fontina isn’t available, other meltable cheeses work beautifully.
• Make it vegetarian: Use vegetable broth instead of beef broth.
• Add mushrooms: Sauté sliced mushrooms with the onions for an earthier flavor.
• Use red wine instead of white: Adds a deeper, more robust flavor.
• Add a touch of balsamic vinegar: A splash added at the end enhances sweetness and depth.
• Gluten-free version: Use gluten-free bread for the topping.
• Creamy twist: Stir in a splash of cream before serving for extra richness.
• Thicker version: Reduce the broth a bit more for a heartier texture.
• Add pancetta or bacon: For a smoky, savory upgrade, cook pancetta with the onions.
• Top with multiple cheeses: Combine Fontina with Parmesan or mozzarella for layered flavor.

Storage/Reheating

Store leftover soup (without bread and cheese) in an airtight container in the refrigerator for up to 4 days.
To reheat, warm on the stovetop over medium heat until hot. Toast fresh bread and melt cheese under the broiler just before serving to retain the best texture.
The soup base can also be frozen for up to 3 months—thaw in the fridge overnight before reheating.

FAQs

Can I make this soup ahead of time?

Yes, the soup base can be made ahead and refrigerated or frozen. Add the bread and cheese fresh when serving.

What’s the best type of onion for this soup?

Yellow or sweet onions caramelize well and provide a rich, sweet base flavor.

Can I skip the wine?

Yes, the wine adds depth but is optional. Just deglaze the pan with a bit of broth instead.

Why use Fontina cheese?

Fontina melts beautifully and has a nutty, creamy flavor that complements the onions perfectly.

Can I use pre-sliced bread?

Yes, just make sure it’s sturdy enough to hold up in the soup and toasts well under the broiler.

Is this soup very salty?

The salt level depends on the broth you use. Taste before adding extra salt, especially with store-bought broth.

Can I use fresh thyme?

Absolutely. Fresh thyme adds a wonderful aroma and flavor, but dried works fine too.

What’s a good side dish for this soup?

A simple green salad, roasted vegetables, or a deli-style sandwich pairs nicely.

Can I make this soup vegan?

Yes. Use olive oil instead of butter, vegetable broth, and a vegan cheese substitute.

Does it have to be broiled?

Broiling melts and browns the cheese perfectly. If you don’t have a broiler, bake the topped soup bowls in a hot oven until cheese melts.

Conclusion

Onion Soup with Fontina is a beautifully simple, soul-warming dish that elevates humble ingredients into something truly special. The sweet, slow-cooked onions and gooey melted Fontina make every bite unforgettable. Whether you’re serving it as a starter or the main event, this cheesy, savory soup is sure to impress and satisfy.

Onion Soup with Fontina

Print Recipe

Pin Recipe

5 Stars 4 Stars 3 Stars 2 Stars 1 Star

No reviews

Onion Soup with Fontina is a rich, comforting twist on classic French onion soup, featuring deeply caramelized onions, savory broth, and a broiled topping of toasted bread and gooey Fontina cheese.

• Author: Laura
• Prep Time: 10 minutes
• Cook Time: 1 hour
• Total Time: 1 hour 10 minutes
• Yield: 4 servings
• Category: Soup
• Method: Stovetop + Broiler
• Cuisine: French-Inspired
• Diet: Vegetarian

Ingredients

• 4 large yellow or sweet onions, thinly sliced
• 2 tbsp unsalted butter
• 1 tbsp olive oil
• 2 cloves garlic, minced
• 1/2 cup dry white wine (optional)
• 6 cups beef or vegetable broth
• 1 tsp fresh thyme (or 1/2 tsp dried thyme)
• 1 bay leaf
• Salt, to taste
• Black pepper, to taste
• 1 baguette or crusty bread, sliced and toasted
• 1 1/2 cups grated Fontina cheese

Cook Mode Prevent your screen from going dark

Instructions

1. In a large pot or Dutch oven, melt butter with olive oil over medium heat.
2. Add sliced onions and cook, stirring often, for 30–40 minutes until caramelized and golden brown.
3. Stir in minced garlic and cook for 1 minute.
4. Deglaze the pot with white wine (if using), scraping up browned bits. Simmer for 2–3 minutes.
5. Add broth, thyme, bay leaf, salt, and pepper. Bring to a simmer and cook for 15–20 minutes. Remove bay leaf.
6. While the soup simmers, toast the bread slices until golden and crisp.
7. Preheat broiler. Ladle soup into oven-safe bowls, top each with toasted bread and a generous amount of grated Fontina.
8. Place bowls under broiler for 2–4 minutes until cheese is melted and bubbly.
9. Serve hot, garnished with fresh thyme if desired.

Notes

• Use vegetable broth for a vegetarian version.
• Deglaze with broth instead of wine if preferred.
• Add mushrooms or pancetta for extra depth.
• Make soup base ahead and add bread/cheese fresh before serving.

Nutrition

• Serving Size: 1 bowl
• Calories: 410
• Sugar: 8g
• Sodium: 960mg
• Fat: 22g
• Saturated Fat: 10g
• Unsaturated Fat: 10g
• Trans Fat: 0g
• Carbohydrates: 34g
• Fiber: 4g
• Protein: 18g
• Cholesterol: 40mg