French onion soup is a timeless dish that offers rich flavors from simple ingredients. Many think of it as a restaurant staple, but it’s entirely doable at home. With a little patience and the right techniques, you’ll be making a soup that can rival any bistro version. This post will walk you through the process, highlighting each key step and sharing a few tips to make your soup even better.
What Makes French Onion Soup Special?
French onion soup has a deep, savory flavor that comes from caramelizing onions slowly and allowing them to release their natural sweetness. The onions combine with broth, herbs, and a touch of wine to create a broth that’s complex without requiring a ton of ingredients. What brings it all together is the topping: toasted bread and melted cheese that adds a satisfying layer.
The good news is that French onion soup doesn’t need fancy ingredients. With onions, broth, bread, and cheese, you’re almost there. The recipe we’ll explore is simple, and each step will help deepen the soup’s flavor.
Ingredients: A Closer Look
- Onions – Yellow onions are ideal here because they have a balanced flavor when cooked down. They’re not too sweet or too sharp, which is perfect for this soup.
- Butter and Oil – The butter provides flavor, while the olive oil helps the onions cook evenly. Using both will prevent the butter from burning while caramelizing.
- Broth – A combination of beef and chicken broth is used for depth. The beef broth adds richness, while the chicken broth keeps the flavor from becoming too strong. If you want a vegetarian version, you can swap in a hearty vegetable broth, though the flavor will be slightly different.
- White Wine (optional) – The wine adds a layer of acidity and helps lift the flavors. You’ll cook off the alcohol, leaving only the flavor. If you don’t want to use wine, you can substitute with a small amount of vinegar or lemon juice for acidity.
- Herbs – Thyme and bay leaf are traditional. They give a light herbal note that complements the onions.
- Bread and Cheese – For the topping, a crusty baguette slice is best because it holds up well without becoming too soggy. Gruyère is the classic cheese for French onion soup; it melts well and has a nutty flavor that works with the onions.
Now that we have the ingredients ready, let’s dive into the steps.
Step 1: Caramelize the Onions
Caramelizing onions is the most important step in this recipe. It’s also the step that requires the most patience. You’ll want to cook the onions slowly over low to medium heat. This process can take around 45 minutes, but the time is worth it.
Tips for Caramelizing Onions:
- Use a wide, heavy-bottomed pot. A wide surface area lets the onions cook evenly.
- Stir occasionally. The onions need time to release their moisture and slowly brown. Stirring too much can stop them from caramelizing.
- Add sugar (optional). A little sugar helps with browning. It’s not essential but can speed up the process slightly.
When the onions are a rich golden brown, you’re ready to move on. The color and sweetness will be your sign that they’re done.
Step 2: Deglaze the Pot
After the onions have caramelized, you’ll deglaze the pot with white wine. This means adding the wine to the hot pan and scraping up any browned bits stuck to the bottom. These bits add flavor, and the acidity of the wine balances the sweetness of the onions. If you’re skipping the wine, you can use a bit of broth instead.
Once you’ve deglazed, let the wine reduce slightly before moving on. This step removes any sharpness from the wine and enhances the flavor.
Step 3: Add Broth and Herbs
With the wine reduced, you’ll add the beef and chicken broth, thyme, and bay leaf. Bring the soup to a gentle simmer and let it cook for about 20 minutes. This allows the flavors to come together and gives the herbs a chance to infuse the broth.
During this time, taste the soup and adjust the seasoning if needed. Salt and pepper are essential here; the right amount brings everything into balance.
Step 4: Prepare the Bread Topping
While the soup is simmering, get the bread and cheese ready. Slice the baguette into thick slices and toast them until they’re golden and crisp. The bread acts as a base for the cheese and won’t get too soggy in the soup if it’s toasted.
Grate the Gruyère cheese so it’s ready for topping. Gruyère melts well and has a nutty taste that works well with the savory broth.
Step 5: Assemble and Broil
Once the soup is ready, ladle it into oven-safe bowls. Place a slice of toasted baguette on top of each bowl and cover it with a generous amount of cheese. Put the bowls under the broiler just until the cheese melts and begins to brown. Watch closely, as broilers can vary in heat and melt cheese quickly.
When the cheese is bubbling and golden, your soup is ready to serve.
Serving and Enjoying French Onion Soup
French onion soup is best enjoyed hot, right out of the oven. The cheese forms a crust over the bowl that’s satisfying to break through with a spoon, and the soup beneath is rich and flavorful. Each bite gives you a mix of melted cheese, crispy bread, and savory broth.
Frequently Asked Questions
1. Can I make French onion soup ahead of time? Yes, the soup base (without the bread and cheese) can be made ahead and stored in the fridge for 2-3 days. Reheat it gently on the stovetop, then add the bread and cheese before serving.
2. Can I freeze French onion soup? Freezing is possible, but keep in mind that the onions might change texture slightly. To freeze, cool the soup base, transfer to a freezer-safe container, and freeze for up to 2 months. When ready to serve, thaw, reheat, and add the toppings.
3. Can I use different types of cheese? Gruyère is the traditional choice, but you can use other cheeses like Emmental, Swiss, or even mozzarella. Each will have a slightly different flavor and melting quality.
4. What’s the best way to store leftover French onion soup? Store any leftover soup in an airtight container in the fridge for up to 3 days. Reheat on the stovetop, and add fresh bread and cheese for serving.
5. Can I make this vegetarian? Yes, you can use vegetable broth in place of the beef and chicken broth. The flavor won’t be as rich, but caramelizing the onions well will still give a good depth.
Tips for Making the Best French Onion Soup
- Take your time with the onions. The key to great flavor is in the caramelization. Rushing this step will affect the depth of flavor in the soup.
- Use good broth. Homemade or high-quality store-bought broth can make a big difference. If using store-bought, go for low-sodium versions so you have control over the salt.
- Toast the bread well. If the bread is too soft, it can get too soggy in the soup. A good toasting gives it structure.
- Experiment with different wines and herbs. While white wine and thyme are traditional, you can use red wine for a bolder flavor or experiment with herbs like rosemary.
Pairing Ideas
French onion soup is satisfying on its own, but it pairs well with some simple sides. A light green salad can be a nice contrast to the rich flavors, or you can serve it with a small charcuterie plate. For drinks, a glass of white wine (like Sauvignon Blanc) complements the soup’s flavors, but it also pairs nicely with sparkling water or herbal tea.
Final Thoughts
Making French onion soup is a rewarding experience. While it may seem like a special occasion dish, it’s actually simple enough for any day. Caramelizing the onions does take time, but each step is straightforward, and the final result is well worth the effort.
The next time you’re in the mood for something warm and comforting, consider making French onion soup. With a handful of ingredients and a little patience, you can create a meal that’s both classic and satisfying. Enjoy!
Print
French Onion Soup
A rich, savory soup with caramelized onions and a bubbly layer of melted Gruyère cheese, perfect for cozying up on chilly days.
- Total Time: 1 hour 30 minutes
- Yield: 4 servings 1x
Ingredients
- 4 large yellow onions, thinly sliced
- 3 tablespoons unsalted butter
- 1 tablespoon olive oil
- 1 teaspoon salt
- 1/2 teaspoon sugar
- 4 cups beef broth (low-sodium)
- 2 cups chicken broth (low-sodium)
- 1/2 cup dry white wine (optional)
- 3 sprigs fresh thyme
- 1 bay leaf
- Salt and freshly ground black pepper, to taste
- 4 slices of baguette, about 1-inch thick
- 1 1/2 cups grated Gruyère cheese
Instructions
- Caramelize the Onions: In a large, heavy-bottomed pot, melt the butter and olive oil over medium heat. Add the onions and salt, stirring to coat. Cook for 30 minutes, stirring occasionally, until the onions turn golden brown. Add the sugar to enhance caramelization, cooking for another 10-15 minutes until the onions are a deep caramel color.
- Deglaze the Pot: Pour in the wine (if using), scraping up any browned bits from the bottom of the pot. Let the wine cook off for 2-3 minutes.
- Simmer the Soup: Add the beef broth, chicken broth, thyme, and bay leaf. Bring to a simmer, cover, and let cook for 20-25 minutes. Discard the thyme and bay leaf, then season with salt and pepper to taste.
- Prepare the Bread Topping: While the soup simmers, preheat the oven broiler. Place the baguette slices on a baking sheet and toast under the broiler until golden, about 1-2 minutes per side.
- Assemble and Broil: Ladle the soup into oven-safe bowls, placing a slice of toasted baguette on top of each. Sprinkle generously with Gruyère cheese. Place the bowls on a baking sheet and broil until the cheese is melted and bubbly, about 2-4 minutes.
- Serve and Enjoy: Carefully remove the bowls from the oven, and serve the soup hot.
- Prep Time: 15 minutes
- Cook Time: 1 hour 15 minutes
- Category: soup
