• Extra-virgin olive oil
• ¾ pound Brussels sprouts, quartered
• ¾ pound Yukon gold potatoes, diced
• 1 yellow onion, thinly sliced
• 1 carrot, diced
• 1 celery stalk, diced
• Salt
• 1 (1-pound) Savoy cabbage, cored and thinly sliced
• 8 cups vegetable broth
• ½ cup dry white wine
• 2 bay leaves
• 2 thick slices of day-old bread
• ⅓ pound fontina cheese, thinly sliced
• Freshly ground black pepper

Heat 3 tablespoons oil in a 5- to 6-quart heavy pot over medium heat. Add Brussels sprouts, potato, onion, carrot and celery. Cook, stirring occasionally, until onion is softened, about 10 minutes. Stir in ¼ teaspoon salt, then add cabbage, broth, wine and bay leaves. Bring to a boil, then reduce heat and cook at a bare simmer, partially covered, stirring occasionally, for 2 hours.

Add bread, pressing with a wooden spoon to moisten and slightly submerge bread. Cover surface of soup with cheese and continue cooking, uncovered, until soup is thick and flavors have blended, about 30 minutes more. Season with salt and pepper. Ladle soup into bowls, generously drizzle with oil and sprinkle with additional pepper. Serve hot.