In keeping with the old Italian tradition of using bread in soups, Cesare places two slices of day-old bread in his bowl of soup — one rubbed with garlic and placed at the bottom of the bowl, and the other sprinkled with Parmesan cheese, broiled until brown and bubbly, then torn into bite-size pieces, to top the warm broth.
Coat the bottom of a stockpot with 3 tablespoons of the olive oil. Add the onion, carrot, and garlic and sauté over medium heat until the vegetables start to soften but do not brown, about 3-4 minutes. Stir occasionally.
Season the chicken with salt and pepper, to taste, and add it to the pot. Turn the chicken pieces over as they start to brown, about 3-4 minutes. When the chicken and the vegetables have browned lightly, add the brandy and reduce by ½.
Using a 6-inch-square piece of cheesecloth, tie together the cloves, bay leaves, cinnamon stick, nutmeg, and rosemary. Add water to cover the chicken and season with salt and pepper, to taste. Add the herb bouquet and celery, bring to a simmer, and cook for 45-60 minutes.
Remove the chicken from the soup. Remove and discard the herb bouquet and the celery. Place the soup in the refrigerator to cool until the fat on top hardens. Remove the soup from the refrigerator and skim the fat off the surface. Reheat.
Meanwhile, preheat the broiler. When the chicken is cool enough to handle, remove the skin, bones, and gristle. Shred the chicken into bite-sized pieces and return it to the soup. Taste and adjust seasoning. Stir in the parsley leaves.
To serve, place a slice of garlic toast in each of 8 ovenproof soup bowls and place the chicken on top. Ladle some of the soup over it and top with another slice of toast. Drizzle the toast with the remaining olive oil and sprinkle with grated Parmesan and pepper, to taste. Place the bowls under the broiler for 2-3 minutes or until the cheese has melted and begun to brown. Serve immediately.