French Onion Soup with Cheese Gratin

Name: French Onion Soup with Cheese Gratin
Prep time: 20 min
Cook time: 60 min
Total time: 80 min
Yield: 4 servings
Cuisine: vegetarian
Ingredients: 1 kg yellow onions; 50 g butter; 1 litre vegetable or beef broth; 150 ml dry white wine; 8 tranches baguette bread; 200 g grated Emmental cheese; 1 pincée salt; 1 pincée freshly ground black pepper; 2 brins fresh thyme; 1 pièce bay leaf

This classic French onion soup is an indispensable comfort dish, rich with caramelized flavors and soul-warming warmth. With its silky broth, melt-in-your-mouth onions, and golden cheese gratin topping, it's a dish that warms the heart and delights the palate with every spoonful.

⏱️80 min

📊Easy

👥4 servings

🍽️Soup

vegetarianbudget-friendlyfamilyréconfortant

Ingredients

1 kgyellow onions
50 gbutter
1 litrevegetable or beef broth
150 mldry white wine
8 tranchesbaguette bread
200 ggrated Emmental cheese
1 pincéesalt
1 pincéefreshly ground black pepper
2 brinsfresh thyme
1 piècebay leaf

Instructions

1PREPARE THE ONIONS: Peel and thinly slice all the onions into regular 5 mm thick rings. You should obtain approximately 800 g of sliced onions. For this step, use a sharp knife for efficient and uniform work that will allow even cooking.
2CARAMELIZE THE ONIONS: Melt the butter over medium-low heat in a large Dutch oven or heavy-bottomed pot. Pour in the sliced onions and mix well to coat them completely in butter. Cook slowly for 35-40 minutes, stirring regularly every 5 minutes. The onions should become translucent, then progressively golden and caramelized with a golden brown color. This slow caramelization develops the natural sugars and creates the characteristic flavor of this soup.
3DEGLAZE WITH WINE: Increase the heat to medium-high and pour the dry white wine over the caramelized onions. Let it reduce for 3-4 minutes, stirring constantly, until the wine is almost completely evaporated and you smell a pleasant alcohol aroma. This step removes excess alcohol and concentrates the wine's flavors.
4ADD THE BROTH: Pour the hot broth (previously warmed in a pot or kettle) over the caramelized onions. Add the fresh thyme sprigs and bay leaf. Bring to a boil, then reduce the heat and let simmer gently for 15-20 minutes covered so the flavors infuse. This cooking allows the aromatics to release their subtle perfumes.
5SEASON AND PREPARE THE GRATIN: Taste your soup and adjust the seasoning with salt and pepper to your preference. Remove the thyme sprigs and bay leaf. Pour the soup into individual bowls or ramekins suitable for the oven. Place 2 slices of baguette bread on top of each bowl, then cover generously with grated Emmental cheese.
6BAKE UNTIL GOLDEN: Preheat your oven to 220°C (thermostat 7-8). Place the soup bowls on the oven rack and let them bake for 8-10 minutes, until the cheese is melted, golden, and slightly crispy at the edges. You can also use the broiler for the last 2-3 minutes to achieve a darker golden color. Remove from the oven carefully as the bowls are very hot, and serve immediately to enjoy the contrast between the hot soup and melted cheese.