Sides · French

Classic French Onion Soup

Sofia Romano

Recipe by Sofia Romano

Pasta & Mediterranean · July 8, 2026

Deeply caramelized onions, a splash of white wine, and rich beef stock come together under a bubbling cap of Gruyere toast. It takes patience at the stove, but the payoff is a bowl of soup that tastes like it came from a Paris bistro. Perfect as a cozy starter or a light meal on its own.

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Classic French Onion Soup

Why you'll love this

  • Rich, restaurant-quality flavor from simple pantry staples.
  • That irresistible molten Gruyere cheese crust on top.
  • Mostly hands-off once the onions caramelize.
  • Easy to make ahead for entertaining.

EveryDayMeal recipe

Classic French Onion Soup

Prep
15m
Cook
55m
Total
70m
Serves
4
Level
Medium

Ingredients

  • 50g butter
  • 1 tbsp olive oil
  • 1 kg onions, thinly sliced
  • 1 tsp sugar
  • 4 garlic cloves, sliced
  • 2 tbsp plain flour
  • 250ml dry white wine
  • 1L hot beef stock
  • 4 slices bread, sliced
  • 140g Gruyere, grated

Equipment

  • Large heavy-based pot
  • Sharp knife
  • Cutting board
  • Ladle
  • Heatproof bowls
  • Grill or broiler

Instructions

  1. Melt the butter with the olive oil in a large heavy-based pot over medium heat, so the butter foams gently without browning.
  2. Add the sliced onions, cover, and cook for 10 minutes until they soften and start to collapse, stirring once or twice so they cook evenly.
  3. Sprinkle in the sugar, then cook uncovered for about 20 minutes more, stirring often, until the onions turn deep golden and jammy. This slow caramelization is what gives the soup its rich, sweet flavor, so lower the heat toward the end if they threaten to catch and burn.
  4. Stir in the sliced garlic for the last couple of minutes, just until fragrant, then sprinkle over the flour and stir well to coat the onions and cook off the raw taste.
  5. Turn up the heat and pour in the wine gradually, stirring constantly to loosen any browned bits from the bottom of the pot, which carry a lot of flavor.
  6. Pour in the hot beef stock, stir, then cover and simmer gently for 15 to 20 minutes so the flavors meld and the soup thickens slightly. Taste and season.
  7. Heat your grill (broiler) and toast the bread slices until golden on both sides.
  8. Ladle the soup into heatproof bowls, float a slice or two of toast on top, and pile on the grated Gruyere. Grill until the cheese is melted, bubbling, and lightly browned, then serve at once.

Tips from the kitchen

  • Slice the onions evenly and thin so they caramelize at the same rate.
  • Don't rush the caramelizing stage. Low and slow builds the deep flavor that defines this soup.
  • Use heatproof bowls that can go under the grill, and place them on a tray for easy handling.

Estimated nutrition per serving: 410 cal · 16g protein · 34g carbs · 22g fat

Make it your own

  • Swap beef stock for vegetable stock to make it vegetarian.
  • Use a splash of dry sherry or brandy in place of some wine for extra depth.
  • Try a mix of Gruyere and Comte or Emmental for the cheese topping.

Storing & make-ahead

Cool the soup (without the toast and cheese) and refrigerate for up to 3 days, or freeze for up to 3 months. Reheat gently on the stove, then add fresh toast and cheese and grill just before serving.

Good to know

Why won't my onions caramelize?
They likely need more time and slightly lower heat. Keep stirring and be patient, as proper caramelization takes at least 20 minutes.
Can I make this without wine?
Yes. Replace the wine with extra stock and a splash of vinegar or a squeeze of lemon to add brightness.
What bread works best?
A sturdy baguette or country loaf holds up best, as it won't turn soggy under the cheese and hot soup.
Can I use pre-caramelized onions?
Absolutely. If you have caramelized onions on hand, this soup comes together in about 25 minutes.

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