Classic French Onion Soup (No Stock)

Ingredients

• 14 g (1 tablespoon)butter
• 2.7–3.6 kg (6–8 pounds)onions, thinly sliced
• 2 teaspoons, plus more as neededkosher salt
• To tastefreshly ground black pepper
• 6 slicescountry-style bread, such as peasant bread
• 80 ml (⅓ cup)sherry
• 15 ml (1 tablespoon), optionalwhite balsamic vinegar or white or red wine vinegar
• 15 ml (1 tablespoon), optionalred wine
• 225–340 g (½–¾ pound)Gruyère or Comté cheese, grated
• 1.4 litres (6 cups)water

Instructions

1. 1

   Soften the onions

   Use a large 6.6–7.6 litre (7–8 quart) pot that can hold all the onions. Set it over medium heat and melt the butter. Add the onions, sprinkle with 2 teaspoons of salt, cover and cook for about 30 minutes, until they have heated through and begun to steam.

2. 2

   Cook them slowly

   Uncover the pot, turn the heat to low and cook the onions for about 3 hours over low to medium-low heat, stirring occasionally. Once they have released their water, you can leave them undisturbed for up to an hour at a time. Season with several grinds of pepper.

3. 3

   Dry the bread

   Meanwhile, heat the oven to 95°C (200°F). Put the bread slices in the oven and leave them until completely dry. They can stay in the oven for a few hours, as the low heat is not high enough to burn them.

4. 4

   Finish the soup

   When the onions have cooked down, their water has evaporated and they are amber-coloured, after 3–4 hours in total, add 1.4 litres (6 cups) of water. Turn the heat to high and bring the soup to a simmer, then reduce the heat to low and stir in the sherry. Taste and adjust the salt and pepper. If the soup is too sweet, add the vinegar; for more depth, add a splash of red wine.

5. 5

   Broil and serve

   Preheat the grill. Divide the soup among bowls, top each with bread and cover with grated cheese. Grill until the cheese has melted and browned nicely, then serve immediately.

What is French onion soup?

French onion soup is a classic French dish of onions cooked until deeply golden, served in a savoury broth with bread and melted cheese. This version is adapted from Michael Ruhlman's Traditional French Onion Soup and takes an especially stripped-back approach: water, rather than stock, lets the onions provide the main flavour.

Slow cooking gives the onions time to become soft and amber, while sherry and a bubbling cheese topping round out the bowl. It is a good choice when you can give the stove a few hours of attention without rushing.

Nutrition and macros by portion

The nutrition label shows one serving as written: 795 calories, 29g protein, 100g carbs, 39g fat.

The onions and bread provide most of the carbohydrates, while the cheese and butter contribute most of the fat; the cheese also supplies much of the protein. Pair a bowl with a crisp salad or other vegetables for a fresh contrast, and remember that the recipe's large onion range and cheese amount affect the nutrition per serving.

The onions do the heavy lifting

Onion quantity: The recipe uses 2.7–3.6 kg, so choose a very large pot that can hold them all at the start. They will shrink substantially as they release and lose their water.

Butter and seasoning: A little butter starts the cooking, while salt helps season the onions from the beginning. Black pepper is added later, once the onions have cooked down.

Let the onions turn amber

Covered start: The first 30 minutes over medium heat warms the large volume of onions and helps them begin to steam. Keep the lid on during this stage.

Slow finish: After uncovering, use low to medium-low heat and stir occasionally. The target is soft, cooked-down onions with their water gone and an amber colour; if they catch on the bottom, lower the heat.

Build flavour without stock

Water base: Add the water only once the onions have cooked down. This keeps the recipe's focus on their concentrated flavour instead of relying on a prepared stock.

Final balance: Sherry brings a rounded note to the soup. The optional vinegar can temper sweetness, while a splash of red wine adds depth if you want it.

Dry bread, better topping

Bread texture: Drying the slices in a low oven makes them sturdy enough to sit on the soup beneath the cheese. Leave them until they feel completely dry rather than just lightly toasted.

Cheese finish: Spread the grated Gruyère or Comté over the bread and grill until melted and browned. Serve straight away so the topping stays hot and the bread does not soften for too long.

Allow plenty of time

The onion cooking takes 3–4 hours in total, and slicing this many onions adds more preparation time. The bread can dry in the oven while the onions cook, so those tasks can overlap.

The soup itself comes together quickly after the onions are ready: add water, simmer, season and finish each bowl under the grill.

What to serve with it

The bread and cheese make the soup substantial enough to serve as a meal. For a contrasting side, add a crisp green salad with a simple vinaigrette.

Serve the bowls as soon as the cheese is browned. Take care when carrying them, as the soup and bowls will be very hot.

Recipe notes & tips

• Use a pot of at least 6.6 litres (7 quarts) so the onions fit before they cook down.
• Slice the onions evenly so they cook at a similar rate.
• Keep the heat low after uncovering and stir occasionally to prevent the onions catching.
• Dry the bread while the onions cook to make better use of the long cooking time.
• Taste the soup before adding vinegar, since the onions' sweetness can vary.
• Grate the cheese yourself if possible so it covers the bread evenly.

Variations

• Choose Comté: Use it in place of Gruyère for a different cheese flavour.
• Adjust the acidity: Add the optional vinegar a little at a time if the soup tastes too sweet.
• Add red wine: Stir in the optional splash for extra depth.
• Use country loaf: Choose a firm country-style bread that can support the cheese topping.
• Make it without wine: Omit the optional red wine and vinegar, keeping the sherry as written.

Common mistakes to avoid

• Pot too small: The onions need to fit at the start; use a 6.6–7.6 litre (7–8 quart) pot.
• Heat too high: Onions can catch before they turn amber; keep them at low to medium-low heat after uncovering.
• Rushing the onions: They need 3–4 hours in total to cook down and colour; wait for the water to evaporate and the onions to turn amber.
• Bread still soft: The topping can become soggy; dry the slices completely in the low oven.
• Over-browning the cheese: It can scorch under the grill; watch the bowls closely and serve once the cheese is melted and nicely browned.
• Seasoning all at once: Salt levels vary; taste after adding the sherry, then adjust the salt and pepper.

How to store

Refrigerate leftover soup without the bread and cheese in a covered container for up to 3 days. Reheat it until piping hot, then top with dried bread and cheese and grill just before serving.

Frequently asked questions