Onion soup

French onion soup

Bowl of French onion soup
Alternative names	Onion soup
Course	Starter (entrée)
Place of origin	France
Region or state	All
Created by	Multiple claims
Serving temperature	Hot
Main ingredients	Onions, , croutons, grated cheese
Variations	Vegan versions

French onion soup (French: soupe à l’oignon [sup a lɔɲɔ̃]) is a type of soup usually based on meat stock and onions, and often served gratinéed with croutons and cheese on top or a large piece of bread. Although ancient in origin, the dish underwent a resurgence of popularity in the 1960s in the United States due to a greater interest in French cuisine. French onion soup is usually served as a starter.

Onion soups have been popular at least as far back as Roman times. Throughout history, they were seen as food for poor people, as onions were plentiful and easy to grow. The modern version of this soup originates in Paris, France in the 18th century, made from beef broth, and caramelized onions. It is often finished by being placed under a grill in a ramekin with croutons and Comté melted on top. The crouton on top is reminiscent of ancient soups (see history of soup).

Recipes for onion soup vary greatly:

Though the liquid is usually meat stock, it may be simply water. Milk may be added. It may be thickened with eggs or flour. It may be gratinéed or not.

Generally, recipes specify that the onions should be cooked slowly, becoming caramelized. Brandy or sherry is added at the end. The soup base is often topped with a slice of bread (a "croute" or "crouton").

For the gratinéed version, the croute is topped with cheese and broiled or baked. The soup is then immediately served in the bowl or ramekin in which it was broiled (or, in the United Kingdom, grilled), baked, or—in family-style—immediately transferred to individual serving bowls via a ladle.