Melt butter in a large saucepan over medium heat; add onion and celery, and saute 5 minutes. Stir in flour, and cook, stirring constantly, 1 minute.
Add broth; bring to a boil, stirring constantly. Reduce heat; simmer 30 minutes.
Stir in peanut butter and half-and-half. Cook over low heat, stirring constantly, 3 to 4 minutes or until heated. Sprinkle with peanuts.
