Warm, rich, and topped with gooey golden cheese, this French onion soup is pure comfort. Simple yet flavorful, it leans on a slow-cooking method to draw out the sweetness of caramelized onions. A touch of apple vinegar adds zing, while toasted bread and melted cheese make it irresistibly cozy.
Here’s the secret to making the best French Onion Soup: it’s all about taking your time with the onions and choosing top-notch ingredients. Good butter, broth, and cheese make all the difference here. Trust me, it’s worth the little splurge.
What’s amazing is how a few humble, budget-friendly ingredients can create something so rich and flavorful. A deep, dark broth bursting with bold, savory goodness, silky caramelized onions, and that glorious, melty cheese bubbling over crunchy bread. It’s the kind of dish that makes you close your eyes and sigh with pure joy.
The real magic happens when you caramelize the onions. It’s a slow process, but the reward is sweet, golden perfection. And let’s not forget the crown jewel, the cheesy toast! Because let’s be honest, French Onion Soup without that gooey, toasty topper is just a sad bowl of onion soup.
Jump to:
⭐Why You'll Love This French Onion Soup
- Fancy but Simple: This soup tastes luxurious but uses everyday ingredients like onions, butter, and stock, impressive yet easy to make.
- Effortless Elegance: The rich flavor comes from slowly caramelizing onions, a simple step that makes all the difference.
- Customizable: Make it your own! Go for deeply caramelized onions or keep it lighter, and try different cheeses or bread to suit your taste.
- Prep Ahead: The soup base can be made in advance, perfect for busy days or entertaining.
- Fits Any Occasion: Whether it’s a cozy dinner or a fancy starter for guests, this soup always feels special.
🧾French Onion Soup Ingredients
Here’s what you need to make this French onion soup:
- Onions: Yellow onions are my favorite, they’re the star of the dish! Caramelizing them brings out their natural sweetness for a rich, velvety soup base. You can use yellow onions, red onions, or sweet onions interchangeably based on your flavor preferences.
- Butter & Oil: I like combining butter and vegetable oil to caramelize the onions. The butter adds richness, and the oil keeps it from burning.
- Salt: A little salt enhances the sweetness of the onions and balances the flavors perfectly.
- Apple Cider Vinegar: Deglazing with apple cider vinegar adds a tangy brightness and lifts all the flavorful bits from the pot. White wine vinegar, red wine vinegar, or wine can provide acidity. Adjust the quantity based on your taste preference.
- Flour: A touch of flour thickens the soup just enough to give it a satisfying texture.
- Vegetable Stock: I love using vegetable stock as the base, it’s savory and pairs beautifully with the sweet onions.
- Bay Leaves: These add a subtle herbal aroma that takes the soup to the next level.
- Garlic: A little garlic rubbed on the toasted bread adds a savory kick that complements the soup’s sweetness.
- Grated Cheese (Gruyère): Topping it with melty, nutty cheese creates a gooey, golden crust that’s irresistible. Swiss cheese, Emmental, or Comté can replace Gruyère. If you're looking for a different flavor, consider using cheddar or mozzarella.
See the recipe card below for a full list of ingredients and measurements.
👩🏻🍳How to Make French Onion Soup
These step-by-step instructions and photos will help you to visualize how to make this recipe. See the recipe card for a printable version of this recipe.
- Heat butter and vegetable oil in a large pot over medium heat, then add the sliced onions.
- Stir the onions occasionally and cook on medium-low heat until golden brown and caramelized, about 30-40 minutes.
- Sprinkle flour over the cooked onions and stir well. Cook for 2-3 minutes to remove the raw taste, then deglaze with apple cider vinegar, scraping up browned bits. Cook for another 2-3 minutes.
- Slowly pour the vegetable stock into the pot, stirring continuously to avoid lumps.
5. Add a few bay leaves and simmer the soup for 15-20 minutes to meld the flavors.
6 Remove the bay leaves and ladle the hot soup into oven-safe bowls.
7. Put a slice of the garlic-rubbed grilled bread on each bowl of soup.
13. Top each bread slice with grated cheese, then broil the bowls until the cheese melts, bubbles, and turns golden brown.
📖Variations
- Herb-Infused: Add fresh thyme, rosemary, or sage for an extra layer of aromatic flavor.
- Mushroom Twist: Sautéed mushrooms bring a delicious earthy, umami kick to the soup.
- Smoky Gouda: Swap Gruyère with smoked Gouda for a unique, smoky flavor.
- Bacon Topping: Crumbled crispy bacon adds a savory, smoky crunch on top.
🍽 What to Serve with French Onion Soup
This French onion soup is amazing on its own, but it’s even better with a side salad like tomato salad, avocado pear salad, or Caesar salad.
For a full meal, pair it with a rotisserie chicken, baked cod, or duck breast with orange sauce.
To drink, a refreshing lemonade is my go-to, and for dessert, nothing beats a cocoa mousse to end the meal on a perfect note.
💭Tips for Success
Slice Evenly: Cut the onions thin and uniform for even caramelization and a smooth, consistent texture in your soup.
Caramelizing Onions: Use a heavy pot for even cooking, and take your time, caramelizing onions to golden perfection takes about 30-40 minutes. Stir occasionally but let them sit to deepen the flavor.
Deglaze the Pot: After caramelizing, use apple cider vinegar (or another flavorful liquid) to scrape up all the tasty browned bits, they add so much flavor!
Season as You Go: Add seasoning at every step, for the onions, after the stock, and before serving, for perfect balance.
Cheese Choice: Gruyère is a classic, but Comté or Emmental work too. Grate it finely for smooth melting and a golden crust.
Broil with Care: Use oven-safe bowls on a baking sheet, and broil until the cheese is bubbly and golden, keep an eye on it!
Make Ahead: Prep the soup base in advance and store in the fridge or freezer. Just reheat and top with fresh bread and cheese before serving.
🍲More Soup Recipes to Try!
Love this French onion soup? You’ll also enjoy these delicious soups:
- Borscht
- Greek Lemon Chicken Soup
- Chili Recipe
- Fabada Asturiana (White Bean Soup)
- Lentil Soup
- Spanish Bean Soup with Clam (Alubias Blancas con Almejas)
🍛More Dinner Recipes!
Here are more of my favorite dinner recipes! Try these:
HUNGRY FOR MORE? Subscribe to my Newsletter and follow along on Facebook, Pinterest, and Instagram for all the latest updates.
📖 Recipe
French Onion Soup
Ingredients
- 1 kg Onions
- 2 tablespoon Butter
- 1 teaspoon Vegetable Oil
- 1 tsp Salt
- 1 tablespoon Apple Cider Vinegar
- 1 tablespoon Flour
- 1 litter Vegetable Stock
- 2 Bay Leaves
- 1 Garlic Clove
- 100 g Grated Cheese
Instructions
- Peel and thinly slice the onions.
- In a large pot, melt the butter and vegetable oil over medium heat and add the sliced onions.
- Stirring occasionally, cook the onions over medium-low heat until they become golden brown and caramelized. This may take around 30-40 minutes.
- Sprinkle flour over the caramelized onions and stir well to combine. Cook for an additional 2-3 minutes to eliminate the raw taste of the flour.
- Pour in the apple cider vinegar to deglaze the pot, scraping up any browned bits from the bottom. Allow the mixture to cook for another 2-3 minutes.
- Slowly pour in the vegetable stock, stirring continuously to avoid lumps.
- Add bay leaves for flavor.
- Bring the soup to a simmer and let it cook for about 15-20 minutes to allow the flavors to combine.
- Taste the soup and season with salt as needed. Adjust according to your preference.
- Grill or toast the bread slices until it's crisp and golden then rub grilled bread slices with garlic cloves for added flavor.
- Remove the bay leaves from the soup and ladle the hot soup into oven-safe bowls.
- Place a piece of the garlic-rubbed grilled bread on top of each bowl of soup.
- Sprinkle a generous amount of grated cheese over the bread in each bowl.
- Place the soup bowls under the broiler until the cheese is melted, bubbly, and golden brown.
- Carefully remove the soup bowls from the oven. Let the soup cool for a minute before serving, as it will be very hot.
- Serve your delicious homemade French Onion Soup hot with the rich flavors of caramelized onions and gooey melted cheese!
Notes
Nutrition
Nutritional information is based on third-party calculations and should be considered an estimate only. Actual nutritional content will vary based upon brands used, measuring methods, cooking method, portion sizes, and more.
Sandra says
This is the best thing for the winter.