5 from 18 votes
French Onion Soup
French Onion Soup features deeply caramelized yellow onions cooked slowly to develop sweet, rich flavor. Combined with garlic, tomato paste, flour, and a blend of vermouth or white wine, brandy, fresh thyme, and beef stock, it forms a savory broth. Topped with toasted baguette slices and melted Gruyère cheese, this classic soup balances sweetness, umami, and a cheesy crust.
Prep Time
20 mins
Cook Time
1 hr 50 mins
Total Time
2 hrs 10 mins
Servings:
6
Calories:
486 kcal
Course:
Soup
Cuisine:
French
Ingredients
For the caramelized onions
- 4 pounds onion sliced thinly from root to stem, yellow
- 2 tablespoons olive oil
- 3 ounces water
- 1 teaspoon salt
- 4 tablespoons butter
Making the soup
- 1 tablespoon flour
- 1 tablespoon tomato paste
- 1/2 cup dry vermouth or 1 cup dry white wine
- 1 tablespoon brandy optional, or sherry
- 1 tablespoon thyme fresh leaves
- 8 cups beef stock see notes below, low-sodium
- 4 cloves garlic minced
- 12 lices baguette 1/2" thick, or enough to mostly cover the soup bowl
- 1 1/2 cups gruyere cheese sliced or shredded
- salt to taste
- black pepper to taste
Instructions
For the caramelized onions
- Heat a large Dutch oven or heavy pot with the olive oil over medium heat. Add the onions, water, and salt and mix to coat. Cover with the lid and cook for 15 minutes.
- Remove the lid and add the butter and continue to cook, stirring occasionally. Keep an eye on the onions and adjust the heat to avoid burning. Add a splash of water every so often to avoid burning if necessary. Full caramelization where the onions become deep brown and sweet will take about 60-90 minutes longer.
Cup of Yum
For the French onion soup
- Once the onions are deeply caramelized add the garlic and cook for 1-2 minutes or until fragrant. Add the tomato paste and cook stirring frequently for 5 minutes. If the paste begins to burn, just add a splash of water.
- Add the flour to the pot and cook for 2 minutes or until all of the flour is no longer white.
- Add the vermouth or wine and bring to a boil while scraping the bottom of the pan with a wooden spoon to dislodge all of the brown bits.
- Once boiling add the beef stock and thyme and bring to a simmer. Cook at a simmer for at least 20 minutes.
- Taste test and adjust salt and pepper to taste. Add the brandy or sherry (optional) and stir to combine. At this point, the soup is done and can be placed into crocks or stored overnight for even more flavor.
- Turn the broiler to high and set the rack so that a sheet pan with soup bowls can fit.
- Ladle the soup into oven-safe soup crocks, leaving enough room for the bread and cheese. Place the crocks onto a baking sheet and place 2 pieces of bread or enough to roughly fit 1 layer on top of each bowl. Sprinkle the Gruyere, dividing evenly into each bowl.
- Broil for 2-3 minutes or until the cheese is bubbly and browned. Garnish with thyme leaves and serve. Enjoy!
Notes
- Prepare the soup at least one day in advance and refrigerate overnight to enhance depth of flavor before broiling the cheese topping.
- Use homemade beef stock or a quality low-sodium beef base for richer taste; boxed stocks are not recommended.
- This recipe yields about six crocks of soup suitable for individual servings.
- Leftovers can be refrigerated for up to five days and reheated gently on the stovetop.
Nutrition Information
Calories
486kcal
(24%)
Carbohydrates
42.5g
(14%)
Protein
18.5g
(37%)
Fat
24.9g
(38%)
Saturated Fat
12.5g
(63%)
Cholesterol
61mg
(20%)
Sodium
735mg
(31%)
Potassium
632mg
(13%)
Fiber
8.3g
(33%)
Sugar
16.9g
(34%)
Calcium
477mg
(48%)
Iron
2mg
(11%)
Nutrition Facts
Serving: 6 Serving
Amount Per Serving
Calories 486
% Daily Value*
| Calories | 486kcal | 24% |
| Carbohydrates | 42.5g | 14% |
| Protein | 18.5g | 37% |
| Fat | 24.9g | 38% |
| Saturated Fat | 12.5g | 63% |
| Cholesterol | 61mg | 20% |
| Sodium | 735mg | 31% |
| Potassium | 632mg | 13% |
| Fiber | 8.3g | 33% |
| Sugar | 16.9g | 34% |
| Calcium | 477mg | 48% |
| Iron | 2mg | 11% |
* Percent Daily Values are based on a 2,000 calorie diet.