This classic French Onion Soup fills the kitchen with a deep, sweet aroma as the onions caramelize. Thin, golden-brown ribbons of onion simmer in rich broth until the flavors turn sweet and savory. A toasty baguette slice topped with bubbling, nutty Gruyère crowns each bowl, adding a crisp, gooey texture. It’s comforting, elegant, and perfect for a chilly evening or a cozy dinner.
Recipe Information
- Prep Time: 15 minutes
- Cook Time: 75 minutes
- Total Time: 90 minutes
- Servings: 4
- Difficulty Level: Medium
Nutrition Information
Approximate per serving:
- Calories per serving: 620 kcal
- Protein: 22 g
- Carbohydrates: 47 g
- Fat: 34 g
- Fiber: 3 g
- Sugar: 8 g
- Sodium: 1,800 mg
Why Make This French Onion Soup
This soup rewards patience with deep, sweet onion flavor and a rich broth. The long caramelization creates a silky texture and a dark, savory taste that canned soup can’t match. Topped with a crisp, cheesy bread round, each spoonful delivers a contrast of silky broth, tender onions, and molten cheese. It’s a simple recipe that feels special for weeknights or dinner guests.
(If you want a heartier meat twist, try the French onion beef short rib soup for a richer experience.)
How to Make French Onion Soup
This section explains the key technique: slowly caramelize the onions to bring out sweetness, then build the soup with wine and broth. Use medium heat and patience—rushing the onions with high heat will burn them and create bitterness. Deglaze the pot with wine (optional) to lift fond and deepen flavor. Finish with toasted baguette and Gruyère under the broiler for that signature melted top.
Ingredients:
- 4 large onions, thinly sliced
- 4 tablespoons unsalted butter
- 1 tablespoon olive oil
- 1 teaspoon salt
- 1 teaspoon sugar
- 4 cups beef broth (or vegetable broth)
- 1/2 cup dry white wine (optional)
- 1 baguette, sliced
- 2 cups grated Gruyère cheese
- Fresh thyme (optional)
- Black pepper to taste
Directions:
Step 1: Preparation
Slice the onions thinly and evenly so they cook at the same rate. Measure out butter, oil, salt, and sugar. Preheat the oven broiler before the final step so it’s ready when the bowls are assembled.
Step 2: Mixing
In a large pot, melt the butter with the olive oil over medium heat. Add the sliced onions, salt, and sugar. Stir to coat the onions evenly. The sugar helps jump-start caramelization but is optional.
Step 3: Cooking
Cook the onions over medium heat, stirring occasionally, until deeply caramelized and golden brown, about 30–40 minutes. Watch closely near the end to prevent burning. Once caramelized, add the white wine (if using) and scrape any browned bits from the bottom. Pour in the beef or vegetable broth, bring to a boil, then reduce heat and simmer for 20–30 minutes. Season with black pepper and add fresh thyme if you like.
Step 4: Finishing
Preheat the broiler. Place baguette slices on a baking sheet and top each with grated Gruyère. Broil briefly until the cheese bubbles and turns golden brown, 1–3 minutes. Ladle the hot soup into bowls and float one or two cheesy baguette slices on top. Serve immediately.
How to Serve French Onion Soup
Serve in oven-safe bowls so you can broil the cheese directly on top. Add a small sprig of thyme or a crack of black pepper before serving. Pair with a simple green salad or roasted vegetables for a balanced meal. For a cozy meal, serve with a glass of the same dry white wine used in the soup.
How to Store French Onion Soup
- Refrigerator: Cool to room temperature and store in an airtight container for up to 3–4 days. Store the cheesy baguette separately to keep it from getting soggy.
- Freezer: Freeze the soup (without bread) in freezer-safe containers for up to 3 months. Thaw overnight in the refrigerator, then reheat gently on the stove.
- Reheating: Warm slowly over low to medium heat, stirring occasionally. If the soup tastes flat after cooling, add a splash of broth or a pinch of salt to brighten it.
Expert Tips for Perfect French Onion Soup
- Slice onions uniformly for even caramelization.
- Use a wide, heavy pot to allow more surface area for browning.
- Keep the heat at medium; too high burns, too low slows caramelization.
- Deglaze with wine or a splash of sherry to lift browned bits and add depth.
- Don’t skip the final broil—bubbly, browned Gruyère creates the classic texture contrast.
- Substitute Swiss or Comté for Gruyère if needed.
- For vegetarian version, use a rich vegetable broth and add a splash of soy sauce or miso for extra umami.
Delicious Variations
- Mushroom and Herb: Add sliced mushrooms during the last 10 minutes of onion cooking for earthiness.
- Vegetarian: Use vegetable broth and add a teaspoon of soy sauce or miso paste for depth.
- Sherry Boost: Replace the white wine with dry sherry for a nuttier finish.
- Garlic and Thyme: Add minced garlic in the last few minutes of onion cooking and more fresh thyme when simmering.
- Beef Short Rib: Slowly braise short rib separately, shred it, and add to bowls for a hearty, meaty version.
Frequently Asked Questions
Q: How do I caramelize onions without burning them?
A: Use medium heat and a wide pot. Stir every few minutes and scrape the bottom to prevent sticking. If they brown too fast, lower the heat. Patience is key—it can take 30–40 minutes.
Q: Can I make this without wine?
A: Yes. Skip the wine and add a splash of extra broth or a teaspoon of balsamic vinegar to add depth. Wine is optional but adds brightness.
Q: Why is my soup bitter?
A: Bitterness usually comes from burned onions. Reduce heat and scrape away any blackened bits. Use fresh onions and stir more often during caramelization.
Q: Can I prepare this ahead of time?
A: Yes. Make the soup up to 3 days ahead and refrigerate. Toast the baguette and broil the cheese just before serving for best texture.
Q: How do I make this lower in sodium?
A: Use low-sodium broth and reduce added salt. Also choose lower-sodium cheese or use a smaller amount of Gruyère. Taste and adjust seasonings at the end.
Q: Can I use a different cheese?
A: Gruyère melts well and has a nutty flavor, but Swiss, Comté, or a sharp fontina also work. Avoid very oily cheeses that don’t brown nicely.
Q: Is this recipe gluten-free?
A: The soup itself is gluten-free if you use gluten-free broth. The baguette contains gluten; swap for gluten-free bread to serve.
Conclusion
This French Onion Soup is a warm, comforting dish that rewards time and care with deep, sweet onion flavor and a satisfying cheesy crust. It’s perfect for cold nights, casual dinners, and small gatherings. For another excellent home-cooked take and extra inspiration, check out French Onion Soup: The Best Homemade Version Around! — it offers helpful notes and variations to try. Enjoy the slow-cooked sweetness and the bubbly cheese topping, and don’t be afraid to make the recipe your own.
Print
Classic French Onion Soup
- Total Time: 90 minutes
- Yield: 4 servings 1x
- Diet: Vegetarian
Description
A warm and comforting classic French onion soup topped with a cheesy baguette slice, perfect for chilly evenings.
Ingredients
- 4 large onions, thinly sliced
- 4 tablespoons unsalted butter
- 1 tablespoon olive oil
- 1 teaspoon salt
- 1 teaspoon sugar
- 4 cups beef broth (or vegetable broth)
- 1/2 cup dry white wine (optional)
- 1 baguette, sliced
- 2 cups grated Gruyère cheese
- Fresh thyme (optional)
- Black pepper to taste
Instructions
- Slice the onions thinly and evenly so they cook at the same rate. Measure out butter, oil, salt, and sugar. Preheat the oven broiler before the final step.
- In a large pot, melt the butter with the olive oil over medium heat. Add the sliced onions, salt, and sugar. Stir to coat the onions evenly.
- Cook the onions over medium heat, stirring occasionally, until deeply caramelized and golden brown, about 30–40 minutes. Add the white wine (if using) and scrape any browned bits from the bottom. Pour in the beef or vegetable broth, boil, then reduce to simmer for 20–30 minutes.
- Preheat the broiler. Place baguette slices on a baking sheet and top each with grated Gruyère. Broil until the cheese bubbles and is golden brown, 1–3 minutes. Ladle the soup into bowls, float cheesy baguette slices on top, and serve immediately.
Notes
For a richer flavor, consider using a splash of sherry or adding herbs like thyme and garlic. Store leftovers separately from cheese bread to maintain texture.
- Prep Time: 15 minutes
- Cook Time: 75 minutes
- Category: Soup
- Method: Simmering and Broiling
- Cuisine: French
Nutrition
- Serving Size: 1 serving
- Calories: 620
- Sugar: 8g
- Sodium: 1800mg
- Fat: 34g
- Saturated Fat: 16g
- Unsaturated Fat: 18g
- Trans Fat: 0g
- Carbohydrates: 47g
- Fiber: 3g
- Protein: 22g
- Cholesterol: 80mg
