Absolutely delicious. Be sure to include the Parmesan cheese, which adds a special touch of its own.
Melt butter in heavy soup pot and saute parsnips and celery, stirring with a wooden spoon until the vegetables are coated with butter. Cover and cook over medium heat for 10 minutes, stirring occasionally. Meanwhile, heat the chicken stock in a saucepan, and after 10 minutes add to the soup pot. Stir well and put 1 cup of the soup (including plenty of solids) into a blender or food processor along with the flour, 1 cup cold water, nutmeg, and salt. Blend at high speed, and return to the soup pot. Add 2 cups water and heat to a good simmer for 5 minutes. Season to taste with pepper. Return another cup of soup to the blender and add parsley. Blend well and return the puree to the soup pot. Heat to a simmer. Just before serving, sprinkle with freshly grated Parmesan cheese.