Celery root—also known as celeriac—is just what it sounds like, the root of a variety of celery plant. Its subtle flavor stands out best in simple preparations like this one, a creamy soup that makes a satisfying supper with a green salad and some crusty bread. This soup freezes well, but the apples should be caramelized just before serving.
Celery Root Puree with Caramelized Apples
2 Tbs. unsalted butter
1 leek, white and pale green parts, chopped
2 celery roots (2 lb./1 kg total), peeled and chopped
3 1⁄2 cups (28 fl. oz./875 ml) vegetable broth
For the caramelized apples:
1 Tbs. unsalted butter
1 small Granny Smith apple, peeled, cored and cut into tiny cubes
1⁄4 tsp. dark brown sugar
2 Tbs. half-and-half
Salt and ground white pepper, to taste
In a large, heavy pot, warm the butter over medium-high heat. Add the leek and sauté until soft, about 4 minutes. Add the celery roots, stir to coat and sauté for 2 minutes. Add the broth and bring to a boil. Reduce the heat to low and simmer until the celery root is very tender, 25 to 30 minutes. Remove from the heat and let cool slightly.
While the soup is cooling, make the caramelized apples. In a frying pan, melt the 1 Tbs. butter over medium-high heat until it foams. Add the apple and sauté for 4 minutes. Sprinkle with the brown sugar, stir to combine and cook until the apples begin to caramelize, about 3 minutes. Remove from the heat and set aside.
Working in batches, puree the soup in a blender. Return to the pot over medium heat, add the half-and-half and return just to a gentle boil. Turn off the heat and season with salt and pepper. Serve, garnished with the caramelized apples. Serves 4.
Find more soup recipes for every season and occasion in our cookbook
Williams-Sonoma Soup of the Day, by Kate McMillan.