Savour the season: Mastering classic French onion soup

Onion soup is an excellent choice for cool autumn and winter days. It's delicious and wonderfully warming. Plus, it's so filling that a second course isn't needed. Preparation is straightforward, and it's best to stick to the traditional French recipe, which they prepare with mastery.

The base of the soup is, naturally, the onion—a vegetable available at every market and relatively inexpensive. Traditionally, yellow onions are used; they have a sharp aroma but impart a slightly sweet taste after longer cooking. The onions should be firm and fresh. Not only is the right choice important, but the preparation of the onion significantly impacts the soup's taste. The French often fry it over low heat for up to an hour to enhance the full aroma and ensure the dish has a rich colour.

The first step in preparing this soup is peeling and slicing the onions into thin slices. Then, sauté them in butter with olive oil or clarified butter, along with a sprig of thyme. This requires patience and is best done for at least half an hour on low heat. After browning the onions, remove the thyme, add broth, and cook for 15 to 20 minutes.

The second important ingredient in the soup is cheese, a French favourite. Traditional recipes call for gruyère, but you can also use emmental or a similar type of cheese. It creates a cheesy crust on top of the soup. The broth can be beef, veal, or chicken. In France, onion soup is seasoned with white wine. To enhance the flavour, you can add a stronger alcohol, like calvados or brandy. The soup is typically served with croutons baked with cheese. A thick, aromatic soup paired with cheesy croutons and an herbal note makes a great duo.

Ingredients:

• 1 kg of onions,
• 3 tablespoons of butter,
• 3 tablespoons of olive oil,
• 1.5 litres of beef broth,
• 250 ml of white wine,
• 150 grams of yellow cheese,
• baguette, sliced,
• garlic clove,
• salt and pepper to taste,
• a few sprigs of thyme,
• calvados or brandy to taste, optional.

Method of preparation:

1. Peel and slice the onions. Melt the butter and olive oil in a pot, and sauté the onions with the thyme on low heat for about half an hour, stirring frequently.
2. Then, increase the heat, add wine, cook for a few minutes, and pour in the boiling broth. Season the soup with spices and cook for about half an hour. At the end of cooking, you can add stronger alcohol if desired.
3. Rub the slices of baguette with the crushed garlic clove and toast them.
4. Pour the soup into small ovenproof bowls. Arrange the croutons on top and sprinkle with cheese.
5. Place the bowls in an oven preheated to 200°C (390°F) and bake for 5 minutes.