Celery root, or celeriac, is exactly what it sounds like: the root of a variety of celery plant. Its subtle flavor stands out best in simple preparations like this one. This soup will freeze well, too — just add the caramelized apples when you’re ready to serve.

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. brown sugar

2 Tbs. half-and-half

Salt and ground white pepper

In a large, heavy pot, warm the butter over medium-high heat. Add the leek and saute until soft, about 4 minutes. Add the celery roots, stir to coat, and saute 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, 25-30 minutes. Remove from the heat and let cool slightly.

While the soup is cooling, make the caramelized apples. In a fry pan, melt the 1 tablespoon butter over medium-high heat until it foams. Add the apple and saute 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.