French onion soup is a lovely dish made from onions that are gently cooked and then simmered in a tasty broth. It's usually served with a piece of bread covered in cheese, baked until the cheese is melted and bubbly, which is called "gratinéed." People have enjoyed onion soups for a very long time, even dating back to ancient Roman times, because onions were always easy to find and inexpensive. While different onion soups were known in France during medieval times, the version most familiar to us today really took shape in the mid-19th century.
Interestingly, onions were often seen as peasant food, but even wealthy households enjoyed fancy versions with expensive spices like saffron back then. A famous story says that King Louis XV's father-in-law, an exiled Polish King, loved an onion soup he tried at an inn so much that he demanded the recipe. However, those early royal recipes didn't usually include the delicious grated cheese topping we expect now.
The modern, cheesy French onion soup we adore became super popular in the restaurants around Les Halles, a big food market in Paris. There, they served it with a generous layer of grated cheese, grilled until it was wonderfully bubbly and melted. This hearty soup became a favorite for everyone and eventually made its way to other countries like Britain and the United States. Today, the main ingredients are gently cooked onions, often in butter, combined with beef, chicken, or veal stock, sometimes enhanced with a little wine or brandy. For that perfect cheesy topping, Gruyère, Comté, or Emmental are popular choices. You can also find other delightful French onion soups, such as the rich Gratinée Lyonnaise or the creamy Velouté Soubise.
