Active Time

　　1 1/4 hr

　　Total Time

　　1 1/4 hr

　　Most chestnut soups are fairly substantial. We've made our version lighter and brothier to serve as a first course for a big meal. Chopped chestnuts mixed with tangy croutons add texture and extra layers of complexity.

　　

Ingredients

Makes 8 to 10 servings

　　

For soup

2 (7 1/2-oz) jars peeled cooked whole chestnuts, rinsed and drained (2 2/3 cups)

　　2 large leeks (white and pale green parts only), coarsely chopped (1 1/4 cups)

　　1 tablespoon olive oil

　　1 tablespoon unsalted butter

　　1 large onion, coarsely chopped (2 cups)

　　2 celery ribs, coarsely chopped (1 1/4 cups)

　　2 medium carrots, coarsely chopped (1 cup)

　　1 1/2 Turkish bay leaves or 1 California

　　1 tablespoon tamari or soy sauce

　　2 1/2 qt water

　　2 teaspoons salt, or to taste

　　1/3 cup chopped fresh flat-leaf parsley

　　1 teaspoon chopped fresh sage

　　2 tablespoons medium-dry Sherry or Madeira

　　1/2 teaspoon black pepper

　　

For topping

2 tablespoons olive oil

　　2 tablespoons unsalted butter

　　1/2 sourdough loaf, crust discarded and bread cut into 1/4-inch cubes (4 cups)

　　1 teaspoon chopped fresh sage

　　2 (7 1/2-oz) jars peeled cooked whole chestnuts, chopped (2 2/3 cups)

　　1 teaspoon flaky sea salt (preferably Maldon)

　　

Make soup:

Step 1

Put oven rack in upper third of oven and preheat oven to 375°F.

　　

Step 2

Spread chestnuts in 1 layer in a large shallow baking pan, then roast in oven until dry and slightly darkened, about 20 minutes.

　　

Step 3

While chestnuts roast, wash leeks in a bowl of cold water, agitating them, then lift out and drain well.

　　

Step 4

Heat oil and butter in a 5- to 6-quart heavy pot over moderately high heat until foam subsides, then sauté leeks, onion, celery, carrots, and bay leaves, stirring occasionally, until vegetables are pale golden, 8 to 10 minutes. Add chestnuts and tamari and cook, stirring, until most of liquid is evaporated, 1 to 2 minutes. Add water (2 1/2 quarts) and salt and simmer, uncovered, stirring occasionally, until vegetables are tender, about 30 minutes. Remove from heat and stir in parsley and sage. Discard bay leaves.

　　

Step 5

Purée soup in 3 batches in a blender until smooth (use caution when blending hot liquids), transferring to a bowl. Pour purée through a medium-mesh sieve into cleaned pot, pressing hard on and then discarding solids. Bring soup to a simmer and stir in Sherry, pepper, and salt to taste, then remove from heat.

　　

Make topping while soup simmers:

Step 6

Heat oil and butter in a 12-inch heavy skillet over moderately high heat until foam subsides, then cook bread cubes with sage, turning occasionally, until croutons are golden, 6 to 10 minutes. Add chestnuts and cook, stirring, 2 minutes. Transfer to a large bowl and toss with sea salt.

　　

Step 7

Ladle soup into bowls and sprinkle each serving with about 1/3 cup topping.

　　Cooks' notes:

　　•Topping can be made 3 days ahead and cooled completely, then kept in an airtight container at room temperature. Reheat in 1 layer on a baking sheet in a 350°F oven until bread is crisp, 10 to 20 minutes.

　　•Soup, without Sherry, can be made 3 days ahead and cooled completely, uncovered, then chilled, covered. Reheat and stir in Sherry before serving.