French Onion Soup

Soupe à l'oignon Also: Soupe à l'oignon gratinée
Gluten: Likely contains restriction
Dairy: Likely contains restriction
Vegetarian: Likely contains restriction

A traditional soup made of caramelized onions and beef stock, topped with a slice of toasted bread and melted Gruyère cheese.

Allergen data cross-referenced against published allergen databases.

Your dietary restrictions

The full allergen breakdown is below. Select your restrictions to see a personalized safety status.

Full allergen breakdown

Ingredients

  • onions
  • beef stock
  • baguette
  • Gruyère cheese (Dairy)
  • butter (Dairy)
  • white wine

Hidden Ingredients

These ingredients are not typically listed on menus but are present in traditional preparations.

  • wheat flour

Allergen Breakdown

Dairy-Free

Likely contains restriction

Contains butter in the soup base and melted Gruyère cheese on top.

Gluten-Free

Likely contains restriction

Topped with a toasted wheat baguette slice; soup may also be thickened with flour.

Peanut-Free

Likely OK

Peanuts are not used in traditional French onion soup preparation.

Tree Nut-Free

Likely OK

Tree nuts are not used in traditional French onion soup preparation.

Shellfish-Free

Likely OK

No shellfish ingredients are used.

Egg-Free

Likely OK

Traditional recipes do not contain egg.

Fish-Free

Likely OK

Made with beef stock; no fish ingredients are used.

Soy-Free

Likely OK

Soy is not a traditional ingredient.

Sesame-Free

Likely OK

Sesame is not used.

Vegetarian

Likely contains restriction

Traditionally prepared using beef stock (fond de bœuf).

Key risk: The soup base often starts with onions caramelized in butter and may be thickened with flour. It is topped with wheat bread and melted cheese, making it highly unsafe for dairy and gluten allergies.

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Important: Dish Scout is a reference guide, not medical advice. Traditional recipes vary by restaurant, region, and chef. Always verify ingredients with restaurant staff before ordering. When in doubt, don't eat it.