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French Red Onion Soup

This elegant French red onion soup offers a sophisticated twist on a classic bistro staple. By using vibrant red onions and a touch of star anise, the broth develops a deep, aromatic complexity that pairs beautifully with the dryness of the red wine. The slow caramelisation process brings out the natural sweetness of the onions, creating a savoury base that is both comforting and refined.

A perfect vegetarian-friendly option for a cold evening, this dish is defined by its indulgent topping of toasted baguette and bubbling Manchego or Gruyère cheese. Served in individual ovenproof bowls, it makes an impressive starter for a dinner party or a satisfying lunch. The combination of the rich, spiced liquid and the crunchy, cheesy crouton provides a wonderful contrast in every spoonful.

Continue reading below

Ingredients for French Red Onion Soup

  • 475ml reduced-sodium chicken broth

  • 475ml water

  • 2 whole star anise

  • 6 black peppercorns

  • 900g red onions, cut into 1/2-inch wedges

  • 45ml olive oil

  • 120ml dry red wine

  • 4 (1-inch-thick) slices of baguette

  • 475ml coarsely grated Manchego or Gruyère (6 to 200g )

How to make French Red Onion Soup

Bring broth, water, spices, and 1/2 teaspoons salt to a boil. Remove from heat and let steep 15 minutes.

Meanwhile, cook onions in oil with 1/4 teaspoons salt in a heavy medium pot over medium heat, covered, stirring occasionally, until deep golden, about 15 minutes. Add wine and boil, uncovered, until reduced to 2 tablespoons , about 1 minute.

Strain broth through a sieve into onion mixture and briskly simmer, uncovered, 10 minutes. Season with salt.

Preheat grill.

Ladle soup into 4 ovenproof bowls set in a 4-sided sheet pan. Place baguette slices on top and sprinkle each with 60g cheese. Grill about 6 inches from heat until cheese is melted and bubbling, about 2 minutes.

Disclaimer

While every effort has been made to ensure the information is accurate and up to date, individual needs may vary and dietary requirements can differ based on personal health conditions. Always check food labels and allergen information before preparing or consuming any recipe. If you have specific health concerns, allergies, intolerances, or are following a medically prescribed diet, seek advice from your GP, pharmacist, or a registered dietitian before making significant changes to your diet or lifestyle.

Article history

The information on this page is peer reviewed by qualified clinicians.

  • 16 Jan 2026 | Originally published

    Authored by:

    UK recipe editors

    Peer reviewed by

    UK recipe editors
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