Ingredient:
2 tablespoons unsalted butter
3 celery stalks with leaves, trimmed and sliced
2 large onions, coarsely chopped
2 sweet apples, such as McIntosh or Fuji, peeled, cored, and cut into 1- to 2-inch cubes
Salt and freshly ground pepper
1 pound celery root, trimmed, peeled, and cut into 1- to 2-inch cubes
1 bay leaf
1 thyme sprig
6 cups chicken broth
Crème fraîche, heavy cream, or sour cream, for serving (optional)
Method:
Melt the butter in a large Dutch oven or soup pot over low heat. Toss in the sliced celery, onions, and apples, season with salt and pepper, and cook, stirring often, for about 5 minutes, or until the vegetables are soft. Add the celery root cubes and turn them around in the butter. Toss the herbs into the pot, add the broth, and bring to a boil. Lower the heat and cook at a gentle simmer for about 30 minutes, or until the celery root is soft enough to mash with the back of a spoon. If you can, pull out the bay leaf and what's left of the thyme.
Working in small batches, puree the soup in a blender or food processor until it is very smooth; or use an immersion blender. (If you're using a processor or immersion blender, you probably won't get a super-smooth soup. If you'd like, you can push the pureed soup through a strainer, but it's really not necessary) Reheat if needed and season to taste with salt and pepper.
Ladle into bowls, and garnish with cream, if you like.
SERVING
For a little richness, you can swirl crème fraîche, heavy cream, or sour cream into the soup at serving time.
