1Saute onion and celery in butter in a large Dutch ov en over medium heat until tender. Transfer sauteed vegetable mixture to the container of an electric blender, and process until smooth.
2Return the pureed mixture to the Dutch oven; add flour, stirring until smooth. Cook 1 minute, stirring constantly. Gradually add chicken broth and water; cook over medium heat until thoroughly heated.
3Add peanut butter, stirring until smooth. Gradually add half and half; cook until thoroughly heated (do not boil(. Ladle into individual soup bowls. Sprinkle each serving with chopped peanuts.