This rich, flavorful soup has a slightly nutty taste and a soft, creamy texture. Note that you may use store-bought, preroasted chestnuts, which come vacuum-packed in jars. However, in our testing, we found that freshly roasted chestnuts tasted best. To roast chestnuts, cut an x through the flat bottom of each nut (this helps with peeling later). Toss chestnuts with salt, pepper, and 1/3 cup canola oil. Spread chestnuts on a baking sheet and roast at 425° until tender, about 25—35 minutes. Return chestnuts to the bowl, toss, and cover bowl tightly with plastic wrap. Cool; then peel.
3 cups roasted, peeled chestnuts, divided
4 tablespoons salted butter, divided
1 small onion, chopped fine
1 carrot, peeled and diced
10 sprigs fresh thyme, chopped
4-1/2 cups chicken stock
1-1/2 cups heavy or light cream
Kosher or sea salt
Freshly ground black pepper
1 cup fresh (or reconstituted dried) wild mushrooms, such as porcini, black trumpet, or chanterelle
Chop chestnuts and set aside.
Melt 2 tablespoons butter in a Dutch oven over medium heat. Add onion and carrot and cook until tender, 8—10 minutes.
Add thyme and stir briefly.
Add chicken stock, heavy cream, and 2-1/2 cups chopped chestnuts. Season to taste with salt and pepper. Then simmer 20—25 minutes.