Chestnut and Celery Root Soup

Ingredients

• 1 tablespoon unsalted butter
• 1 1/2 teaspoons extra-virgin olive oil
• 1/2 medium yellow onion, chopped
• 1/2 cup peeled and coarsely chopped celery root
• 1 1/2 cups bottled or vacuum-packed steamed chestnuts (about 10 oz.)
• 1/2 teaspoon minced fresh thyme
• 3 cups chicken or vegetable stock, homemade or canned reduced-sodium
• About 1 tsp. kosher or sea salt
• About 1/4 tsp. pepper
• 6 tablespoons heavy cream, divided
• Thinly sliced chives, plus chive-blossom petals if you have them, for garnish

Preparation

1. 1. Warm butter and oil in a medium saucepan over medium heat. Add onion and cook until soft, 10 minutes. Add celery root, chestnuts, thyme, and stock. Bring to a simmer, then cover partially and simmer gently until celery root is tender, 20 to 25 minutes.
2. 2. Purée soup in a blender in batches. Stir in 1 tsp. salt, 1/4 tsp. pepper, and 2 tbsp. cream.
3. 3. Whisk remaining cream into soft peaks. Season soup with salt and pepper. Serve 1/4-cup portions in espresso cups or teacups, topped with cream and chives.
4. Make ahead: Through step 2, up to 1 day, covered and chilled. Reheat over medium heat.
5. Note: Nutritional analysis is per serving.