Good-quality coarse country bread is essential for making this soup. Ideally, the bread should be a day old, as a drier loaf will absorb more liquid.
Recipe courtesy of Williams-Sonoma and adapted from Williams-Sonoma Lifestyles Series, Soup for Supper, by Joyce Goldstein (Time-Life Books, 1998).
- 4 tablespoons (1/2 stick) unsalted butter
- 6 large yellow onions, thinly sliced
- 6 tablespoons chopped fresh basil
- 5 cups water, vegetable stock or chicken stock or canned broth
- Salt and freshly ground pepper, to taste
- 4 thick slices coarse country bread, preferably day-old, cut into 1-inch cubes
- 1/2 cup grated Parmigiano-Reggiano or shredded fontina cheese
- 1 In a large sauté pan over low heat, melt the butter. Add the onions and sauté very slowly, stirring often, until caramelized, about 45 minutes. The onions must be sweet and golden but not brown. Stir in 2 tablespoons of the basil and cook for 5 minutes to flavor the onions. Add the water, cover and simmer until the onions are quite tender, about 30 minutes more.
- 2 Meanwhile, preheat an oven to 350°F.
- 3 When the onion mixture is ready, season with salt and pepper and remove from the heat. Place individual ovenproof bowls on 1 or 2 baking sheets and evenly divide the bread cubes among them. Top with the hot onion mixture and then the cheese.
- 4 Bake until the cheese melts and the soup is piping hot, 10 to 20 minutes. Garnish with the remaining 4 tablespoons basil and serve immediately. Serves 6.