French onion soup

This classic French soup is so quick and simple to make, and you can even prepare it ahead of time — when you’re ready to eat, just warm it through and finish with your croutons. French onion soup is the ultimate comfort classic: rich, deeply savoury and built on the simple magic of slowly caramelised onions. With its golden broth, a splash of wine and plenty of melted cheese bubbling over crisp toasted bread, it feels indulgent yet wonderfully rustic.

Despite its elegant reputation, it’s surprisingly straightforward to make at home, and the long, gentle cooking transforms everyday ingredients into something truly special. Whether you’re serving it as a cosy starter or a comforting main, this French onion soup is a timeless favourite that never disappoints.

French onion soup

French onion soup with mustard cheesy croutons

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Cook Time 40 minutes
Course Soup
Cuisine French
Servings 4 people

Ingredients
  

  • 40 g unsalted butter
  • 4 large onion, halved and thinly sliced
  • 1 tbsp soft brown sugar
  • 1 tsp garlic paste
  • 150 ml white wine
  • 1 litre beef stock
  • 1 tbsp thyme
  • 1 bay leaf
  • 1 tbsp yeast extract
  • 2 tbsp cornflour, mixed with 3 tbsp water to form a thick paste
  • Season with salt and pepper

Mustard cheesy croutons

  • 1 french stick, cut into thick slices
  • dijon mustard
  • cheddar cheese

Instructions
 

  • Heat the butter in a large saucepan over a medium heat, when the butter has melted add the onions, lower the heat and cook the onions for around 8mins until they begin to soften.
  • Add the sugar and cook for another 5mins until the onions are caramelised. Then add the garlic and stir for another minute.
  • Gradually add the wine and reduce by half.
  • Then add the beef stock, thyme, bay leaf and yeast extract and bring to a boil
  • Then add the cornflour and stir until all combined, cover and simmer for around 10-15mins.
  • In the meantime, make the croutons. Preheat the grill and toast the slices on one side.
  • On the uncooked side spread some mustard very thinly, sprinkle with the cheese and pop back under the grill until the cheese has melted.
  • Divide the soup with into bowls, serve immediately with the croutons on the side.