Meltingly tender onions, meaty stock, and rich, nutty melted cheese—these are the indispensable elements that make this boldly flavored soup a hallmark of French cuisine—and a favorite of American tables, too. Take the time to make your own stock and you will be rewarded with deep flavor and savory goodness.

French Onion Soup

2 Tbs. unsalted butter

2 1/2 lbs. yellow onions, halved and thinly sliced

1 Tbs. all-purpose flour

1 cup dry white wine

8 cups beef stock

2 tsp. minced fresh thyme, or 1 tsp. dried

1 bay leaf

Kosher salt and freshly ground pepper

1 crusty baguette

2 2/3 cups shredded Gruyère cheese

In a large, heavy sauté pan, melt the butter over medium heat. Add the onions, stir well, cover and cook for 5 minutes. Uncover, reduce the heat to medium-low and cook, stirring occasionally, until tender and deep golden brown, about 30 minutes.

Sprinkle the flour over the onions and stir until combined. Gradually stir in the wine, then the stock, and finally the thyme and bay leaf. Bring to a boil over high heat, reduce the heat to medium-low, and simmer, uncovered, until slightly reduced, about 30 minutes. Season with salt and pepper. Discard the bay leaf.

Meanwhile, preheat a broiler. Have ready eight 1 1/2-cup broilerproof soup crocks. Cut the baguette into 16 slices, sizing them so that 2 slices will fit inside each crock. Arrange the bread slices on a baking sheet and broil, turning once, until lightly toasted on both sides, about 1 minute total. Set the slices aside. Position the oven rack about 12 inches from the heat source, and leave the broiler on.

Ladle the hot soup into the crocks. Place 2 toasted bread slices, overlapping if necessary, on top of the soup and sprinkle each crock evenly with about 1/3 cup of the Gruyère. Broil until the cheese is bubbling, about 2 minutes. Serve at once. Serves 8.

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