Chestnut Soup With Sourdough Sage Croutons Recipe

Make the soup: Put oven rack in upper third of oven and preheat oven to 375 degrees F.

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

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

Heat oil and butter in a 5- to 6-quart heavy pot over moderately high heat until foam subsides, then saute 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 the water 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.

Puree soup in 3 batches in a blender until smooth (use caution when blending hot liquids), transferring to a bowl. Pour puree 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: 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.

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