French Onion Soup with Thyme and Gruyère Toasts

The onions are the main cooking task in this French onion soup. Let them become deeply golden before adding garlic, thyme, white wine and stock. Toasted bread and melted cheese are prepared separately at serving time, not stored in the soup.

Ingredients for the soup base

• 6 large onions, thinly sliced
• 3 cloves garlic, minced
• 1.2 litres beef stock (or vegetable stock)
• 150ml dry white wine
• 3 tbsp butter
• 1 tbsp extra virgin olive oil
• 2 tsp fresh thyme leaves
• 1 bay leaf
• 1 tsp sugar
• Sea salt & black pepper

For serving: baguette slices and Gruyère cheese. The original recipe does not specify quantities for these toppings; prepare enough for the bowls you are serving.

Cook the onions until deeply golden

1. Heat the butter and olive oil in a large pot over medium heat.
2. Add the sliced onions and sugar. Cook, stirring occasionally, until the onions are soft and deeply golden brown. The original estimate is 30–40 minutes, but the quantity of onions, pan and heat can make this take longer. Lower the heat if they begin to scorch rather than brown.
3. Add the garlic and thyme and cook for 1 minute.
4. Pour in the white wine and simmer for 3–4 minutes to reduce it.
5. Add the beef or vegetable stock and bay leaf. Bring to a boil, then reduce the heat and simmer for 25–30 minutes.
6. Remove the bay leaf. Taste and season with salt and pepper.

Plan for the full cooking time

Browning the onions and simmering the broth are separate stages. The 25–30 minute simmer does not include slicing six onions, browning them, cooking the garlic or reducing the wine. Use the onions' color and texture as well as the clock.

Make the cheese toasts fresh

1. Toast baguette slices.
2. Top with Gruyère and place under the grill or broiler until melted, watching closely.
3. Ladle hot soup into bowls and place the cheese toasts on top just before serving.

The original variations allow sourdough instead of baguette and Emmental, Comté or cheddar instead of Gruyère.

Stock and wine notes

Choose the listed beef or vegetable stock option according to your preference. Butter and the cheese topping contain dairy. White wine is part of the soup base; reducing it does not guarantee an alcohol-free finished soup.

Preparing the base for later

Keep bread and cheese separate from the stored soup. Divide leftover base into clean, shallow containers and refrigerate promptly. If freezing, use freezer-safe containers or soup trays, leave expansion space according to their instructions and label the portions.

Transfer frozen tray portions to a freezer bag or container once solid. Thaw in the fridge and reheat in a pot, stirring until hot throughout. Prepare the cheese toasts fresh after reheating so they do not sit soaking in the stored broth.

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