Makes 8-9 servings.
I adapted this from Epicurious.
- 1/4 cup (1/2 stick) butter
- 4 cups 1/2-inch cubes peeled celery root (from one 1 1/4-pound celery root)
- 3 cups 1/2-inch cubes peeled cored apples (from about 2 medium)
- 1 1/2 cups chopped onion (about 1 large)
- 2 cups (or more) low-salt chicken broth
- Melt butter in heavy large pot over medium heat. Add celery root, apples, and onion. Cook until apples and some of celery root are translucent (do not brown), stirring often, about 15 minutes.
- Add 4 cups broth. Cover and bring to simmer. Reduce heat to medium-low; simmer covered until celery root and apples are soft, stirring occasionally, about 25 minutes.
- Remove from heat; cool slightly.
- Working in batches, puree soup in blender until smooth, adding more broth by 1/4 cupfuls to thin to desired consistency. Return soup to pot. Season to taste with salt and pepper.