This soup is synonymous with bistro fare in France and here is a simplified recipe. As the name implies, the flavor comes from the onions. The trick is to ensure you cook the onions slow and low, until they are really caramelized so be sure to take the time it takes to brown them properly. Once you’ve done that, it’s a cinch.
If you want to do the melted cheese-bread topping, you will need ovenproof bowls for serving. If you don’t have the bowls, do not worry. Put toasted rounds of baguette in the bottom of your soup bowl, top with grated cheese and pour over the hot onion soup. Different, but just as yummy.
French Onion Soup
Soupe gratinée à l’oignon
50 g unsalted butter
1 tablespoon olive oil
3 large onions, about 1.3 kg, thinly sliced
2 garlic cloves, crushed
1 tablespoon plain flour
1 litre beef, chicken or vegetable stock
600 ml dry white wine
1 fresh bay leaf
2 sprigs of thyme
1 baguette, sliced
about 180 g Gruyère cheese, finely grated
coarse sea salt and freshly ground black pepper
Put the butter and oil in a large saucepan and melt over medium heat. Add the onions and cook over low heat until deep golden and caramelized; the time depends on your pan so I cannot say exactly. Use your eyes, and taste.
Once the onions are fully cooked, add the garlic and flour and cook, stirring for about 1 minute. Add the stock, wine, bay leaf and thyme. Season with salt and pepper and bring to a boil. Boil for 1 minute, then lower the heat and simmer very gently for 20 minutes. Taste and adjust the seasoning. (At this point, the soup will be cooked, but standing time will improve the flavor – at least 30 minutes but, like any soup, this is always best the next day.)
Before serving, turn on the grill or the broiler.
Put the baguette slices on a baking sheet and brown under the grill/broiler until lightly toasted. Set aside.
To serve, ladle the hot soup into ovenproof bowls and top with a few toasted baguette rounds. Sprinkle grated cheese over the top and set on a baking tray to make it easier to get in and out of the oven. Cook under the still-hot grill until browned and bubbling. Serve immediately, taking care because the bowls will be hot!
photo by Peter Cassidy © Ryland Peters & Small, from Bistro by Laura Washburn Hutton, published by Ryland Peters & Small (£9.99)