French Onion Soup is a warm and comforting dish made with sweet caramelized onions, rich broth, and topped with melted cheese and crunchy bread. It’s like a hug in a bowl!
I love how easy it is to make this soup. Just let the onions cook down until they’re golden and delicious. Plus, that cheesy top? It’s basically the cherry on top for your taste buds! 😋
Key Ingredients & Substitutions
Yellow Onions: These are best for French onion soup since they become sweet when caramelized. If you can’t find yellow onions, you can use white ones, but they might be a bit sharper in taste.
Butter: Unsalted butter helps control the saltiness of the soup. You could use olive oil for a dairy-free option, or a combination of both for flavor.
Beef Broth: This is key for a rich flavor, but if you want a lighter soup, try a mix of beef and chicken broth or even vegetable broth! Just keep in mind the taste will be different.
Gruyère Cheese: This cheese gives a fantastic melting quality. If you can’t find it, Swiss cheese or Emmental are great substitutes. Even mozzarella could work, though it won’t have the same flavor profile.
Baguette: Any crusty bread works great! For a gluten-free option, look for gluten-free baguettes or use toasted gluten-free bread as a base.
How Do I Get Perfectly Caramelized Onions?
Caramelizing onions is all about low and slow cooking. Here’s how you can do it right:
- Heat a heavy pot over medium heat and add butter and oil.
- Once melted, add your sliced onions and stir to coat. Keep the heat at medium-low to allow them to cook evenly.
- Cook for about 25-30 minutes, stirring frequently to avoid burning. Patience is key here!
- Midway through, sprinkle in the sugar to help enhance the sweetness and deepen the color.
- Watch as they turn golden brown, and enjoy the sweet aroma that fills your kitchen!
How to Make French Onion Soup
Ingredients You’ll Need:
For the Soup:
- 4 large yellow onions, thinly sliced
- 3 tablespoons unsalted butter
- 1 tablespoon olive oil
- 1 teaspoon sugar
- 2 cloves garlic, minced
- 1/2 cup dry white wine (optional)
- 8 cups beef broth (or a mix of beef and chicken broth for a lighter taste)
- 2 teaspoons fresh thyme leaves (or 1 teaspoon dried thyme)
- 1 bay leaf
- Salt and freshly ground black pepper, to taste
For the Toppings:
- 1 baguette, sliced into 1/2-inch thick rounds
- 2 cups grated Gruyère cheese (can substitute with Swiss or Emmental)
- Fresh thyme sprigs for garnish (optional)
How Much Time Will You Need?
This recipe will take about 1 hour and 15 minutes to prepare and cook. You’ll spend about 30 minutes caramelizing the onions and another 30 minutes to let the soup simmer and meld the flavors together. Plus a few minutes to broil the cheesy topping at the end!
Step-by-Step Instructions:
1. Sauté the Onions:
In a large heavy-bottomed pot or Dutch oven, heat the butter and olive oil over medium heat until it melts. Add the sliced onions and stir them to coat in the butter and oil. Cook the onions slowly, stirring frequently, for about 25-30 minutes. You want them to become deeply caramelized and golden brown. Halfway through, sprinkle in the sugar to help enhance the natural sweetness of the onions.
2. Add Garlic and Deglaze:
Once your onions are a beautiful golden color, add the minced garlic and cook for another minute until it’s fragrant. Pour in the white wine to deglaze the pan, scraping up any tasty browned bits stuck to the bottom. Let it simmer until the wine reduces by half.
3. Make the Soup Base:
Add the beef broth, thyme, and bay leaf to the pot. Bring the soup to a gentle simmer and cook uncovered for about 30 minutes. This will let the delicious flavors meld together. Don’t forget to stir occasionally!
4. Season the Soup:
After simmering, remove the bay leaf and taste your soup. Season it with salt and freshly ground black pepper to your liking.
5. Prepare the Bread:
While the soup is simmering, preheat your oven’s broiler. Arrange the baguette slices on a baking sheet and toast them under the broiler until they are lightly golden on both sides. Watch them closely so they don’t burn!
6. Assemble the Bowls:
Once the soup is ready, ladle it into oven-safe bowls. Place one or two of the toasted baguette slices on top of each bowl of soup. Then generously sprinkle the grated Gruyère cheese over the bread slices.
7. Broil the Cheese:
Place the bowls on a baking sheet and transfer them to the oven under the broiler. Broil until the cheese is melted, bubbly, and golden brown, which should take about 2-4 minutes. Keep a close eye on them; they can go from perfect to burnt very quickly!
8. Serve and Enjoy:
Carefully remove the bowls from the oven (they’ll be hot!). If you like, garnish with fresh thyme sprigs for a nice touch. Serve immediately and enjoy the warm, comforting layers of rich, savory caramelized onion soup with cheesy, toasted bread on top!
Can I Use Frozen Onions for This Recipe?
While fresh onions yield the best flavor and texture, you can use frozen onions in a pinch. Just ensure they’re thawed and drained of excess moisture before cooking to achieve that perfect caramelization.
What Can I Substitute for Gruyère Cheese?
If you can’t find Gruyère cheese, Swiss, Emmental, or even mozzarella can work well as substitutes. Keep in mind that while they melt nicely, the flavor may differ slightly, so choose based on your preference!
How Should I Store Leftover Soup?
Store any leftover French onion soup in an airtight container in the fridge for up to 3 days. If you have leftovers of the cheesy bread topping, keep them separate to maintain their texture. Reheat the soup gently on the stove or in the microwave.
Can I Make This Soup Vegetarian?
Absolutely! Simply substitute the beef broth with vegetable broth, and you’ll still achieve a delicious and hearty soup. You can add a splash of soy sauce or miso to deepen the flavor.
