Few dishes can match the depth and elegance of a well-made French Onion Soup. With deeply caramelized onions simmered in rich broth and topped with a crisp baguette slice blanketed in melted Gruyère, this dish brings all the warmth and charm of a Parisian café into your own kitchen. 🇫🇷
Whether you’re preparing a cozy dinner for two or serving a special starter at a dinner party, this timeless soup delivers robust flavor and pure comfort in every spoonful. ✨
Why You’ll Love This Soup 💛
✅ Deep, Savory Flavor – Caramelized onions add unmatched richness
✅ Impressive but Easy – Simple ingredients, big results
✅ Perfect for Chilly Nights – Warm, cheesy, and satisfying
✅ Freezer-Friendly – Great to make ahead
✅ Restaurant-Quality at Home – With just one pot and a broiler!
Ingredients You’ll Need 🛒
- 3 pounds yellow onions – About 3–4 large; sliced thin 🧅
- 3 tbsp unsalted butter – For rich caramelization
- 1 tbsp extra virgin olive oil – Helps onions cook evenly
- 2 cloves garlic, minced – Adds a savory base
- 2 tbsp all-purpose flour – Lightly thickens the broth
- ½ cup dry white wine – Adds brightness and depth 🍷
- 6 cups low-sodium beef broth – Or vegetable broth for a vegetarian version
- ½ tsp salt + ¼ tsp black pepper – Adjust to taste
- 4 sprigs fresh thyme or 1 tsp dried thyme – For herby aroma 🌿
- 2 bay leaves – Infuses earthy depth
- 8 slices baguette – Toasted for topping
- 2 oz Gruyère cheese, shredded – Or use Swiss or white cheddar 🧀
Optional Add-ons:
– Extra Parmesan for more umami
– Dash of Worcestershire sauce for richness
– Fresh thyme for garnish 🌱
How to Make French Onion Soup 🧑🍳
Step 1: Caramelize the Onions
In a heavy-bottomed pot, heat butter and olive oil over medium. Add thinly sliced onions and cook 25–30 minutes, stirring often, until soft, deep golden, and sweet. This step is key—don’t rush it! 🕰️
Step 2: Add Garlic & Flour
Stir in garlic and flour. Cook for 1 minute, stirring constantly, to remove raw flour taste.
Step 3: Deglaze with Wine
Pour in white wine and simmer 1–2 minutes. Scrape up any browned bits from the bottom—these add rich flavor.
Step 4: Simmer the Soup
Add broth, thyme, bay leaves, salt, and pepper. Bring to a gentle simmer. Reduce heat and let it cook 30 minutes, uncovered, stirring occasionally.
Step 5: Toast the Baguette
Preheat oven to 400°F. Arrange baguette slices on a baking sheet and toast for 5–6 minutes, until golden and crisp.
Step 6: Broil the Topping
Ladle hot soup into oven-safe bowls placed on a baking sheet. Top each with 2 toasted baguette slices and a generous sprinkle of Gruyère.
Step 7: Broil Until Bubbly
Broil at 425°F for 2–4 minutes, watching closely. When cheese is melted and golden, remove carefully.
If bowls aren’t broiler-safe: Melt the cheese separately on the baguette slices and serve them on top or alongside the soup.
Tips & Substitutions 💡
- Vegetarian? Use vegetable broth instead of beef
- No Gruyère? Try Swiss, white cheddar, or even provolone
- Make-Ahead Friendly – Store soup and bread separately; broil when ready to serve
- Go Extra Cheesy – Add grated Parmesan under the Gruyère
- Enhance Umami – Stir in a splash of soy sauce or Worcestershire
Serving Suggestions 🍽️
- As a Starter – Pair with a leafy green salad and light vinaigrette
- For Dinner – Add a glass of wine and serve with a hearty entrée
- With Sides – Crusty garlic bread or roasted vegetables
- Fancy Finish – Garnish with thyme and cracked pepper
Storage & Reheating 🧊
- Refrigerate: Soup (without bread/cheese) lasts up to 4 days
- Freeze: Store in portions, freeze up to 3 months
- Reheat: Simmer on the stove until hot; broil fresh toppings just before serving
FAQs About French Onion Soup ❓
Q: Do I need wine in the recipe?
A: Wine adds depth but can be skipped or swapped with balsamic or white wine vinegar.
Q: What’s the best cheese for topping?
A: Gruyère is traditional, but Swiss or white cheddar also melt beautifully.
Q: Can I make this gluten-free?
A: Yes—use gluten-free flour and bread for the topping.
Q: Can I prep it ahead for a party?
A: Definitely! Make the soup and toast the bread in advance; assemble and broil just before serving.
Final Thoughts 🧅🔥
French Onion Soup is more than just a meal—it’s a cozy experience, a savory indulgence that turns humble onions into something truly spectacular. The slow caramelization brings out their natural sweetness, while the rich broth, wine, and herbs create a base that’s both rustic and refined. And of course, that bubbling cheese crust takes everything over the top. 🤤
What makes this dish unforgettable is the balance—it’s both comforting and elegant, simple and luxurious. It fills the house with warmth as it simmers, and the final presentation feels like something you’d order at a charming bistro in Paris. 🥖🇫🇷
Whether you’re making it for a special dinner or just treating yourself on a cold evening, this soup brings people together and invites them to slow down and savor. Once you’ve tasted it from scratch, you’ll never go back to canned versions again. 💛🍲
Short version
French Onion Soup
Ingredients
- 3 pounds yellow onions 3-4 large onions
- 3 tablespoons unsalted butter
- 1 tablespoon extra virgin olive oil
- 2 cloves garlic minced
- 2 tablespoons all-purpose flour
- ½ cup dry white wine
- 6 cups low sodium beef broth or stock
- ½ teaspoon salt or to taste
- ¼ teaspoon black pepper or to taste
- 4 sprigs fresh thyme or 1 teaspoon dried thyme
- 2 bay leaves
- 8 slices baguette
- 2 ounces Gruyere cheese shredded
Instructions
- Slice the onions into even ¼-inch thick rings or half-moons for uniform cooking and the best caramelization. In a large Dutch oven or another heavy-bottomed pot, heat the butter and olive oil over medium heat until the butter is melted and the mixture is hot and shimmering.
- Add the sliced onions to the pot and begin cooking, stirring every few minutes to prevent sticking. Let the onions cook slowly for 25 to 30 minutes, until they become deeply golden, very soft, and sweetly caramelized. As the onions near the end of their cook time, stir them more frequently to prevent burning and ensure they brown evenly without scorching.
- Once the onions are caramelized, stir in the minced garlic and flour. Cook for about one minute, stirring constantly to eliminate any raw flour taste and help the soup thicken slightly later on.
- Pour in the white wine and stir as it simmers for 1 to 2 minutes, scraping up any browned bits from the bottom of the pot. These bits add depth and richness to the final flavor of the soup.
- Add the beef broth or stock, a pinch of salt and pepper, thyme sprigs or dried thyme, and bay leaves. Increase the heat and bring the mixture to a gentle simmer. Once simmering, reduce the heat to maintain a low, steady bubble. Let the soup cook uncovered for about 30 minutes, stirring occasionally to develop the flavor and allow it to reduce slightly.
- While the soup simmers, preheat your oven to 400 degrees Fahrenheit. Arrange slices of baguette on a baking sheet and toast them in the oven for 5 to 6 minutes, or until the edges are crisp and golden brown. This creates the perfect base for the melted cheese topping.
- Taste the soup and adjust the seasoning with more salt and pepper if needed. Remove and discard the bay leaves and thyme sprigs before serving.
- Preheat the oven broiler to 425 degrees Fahrenheit. Set four oven-safe soup bowls on a sturdy rimmed baking sheet. Carefully ladle the hot soup into each bowl, then place two toasted baguette slices on top of each one, with the more toasted side facing down. Generously sprinkle shredded Gruyere cheese over the bread.
- If your bowls are not broiler-safe, simply flip the baguette slices over on the baking sheet, top them with Gruyere, and broil them separately for 2 to 4 minutes until the cheese is melted and lightly browned. Serve the cheesy toasts alongside the soup.
- Place the baking sheet with the filled soup bowls under the broiler for 2 to 4 minutes, watching closely to prevent burning. When the cheese is melted and bubbling with golden edges, remove the bowls carefully. Garnish with fresh thyme if desired, and serve immediately. Be cautious—the bowls will be extremely hot after broiling.
Notes
If you don’t have Gruyere cheese on hand or prefer another option, white cheddar makes a great alternative. It melts well and brings a sharp, savory note to the dish. For even more depth of flavor, try adding a small sprinkle of grated Parmesan on top of the shredded cheese before broiling.
To prepare this soup ahead of time, you can cook the entire soup and toast the baguette slices up to one day in advance. Store the toasted bread in an airtight container at room temperature so it stays crisp. Let the soup cool and transfer it to a sealed container in the refrigerator. When you’re ready to serve, reheat the soup on the stovetop until hot. Then top each bowl with the toasted baguette slices and shredded cheese, and broil according to the recipe instructions until the cheese is melted and bubbly.
