In a heavy saucepan or stockpot over medium heat, sauté onion and celery in butter until soft. Do allow to brown.
Sprinkle flour over sautéed vegetables and stir to combine. Stir to saute for one minute.
Add chicken or vegetable stock to vegetables. Bring mixture to boil, stirring constantly. Remove from heat.
Allow the vegetable mixture to cool to a temperature that is safe to work with before proceeding to the next step.
Option 1: Puree the cooled soup in the saucepan with a hand blender until smooth. Option 2: Puree the cooled soup in a blender and return to saucepan.
Into the pureed soup in pan, add the peanut butter and half & half. Stir until peanut butter has completely dissolved into the soup.
Stir in lemon juice, kosher salt, hot pepper sauce, and brown sugar.
Return pan to heat only to warm to soup to serving temperature. DO NOT BOIL!
Serve warm or cold. Garnish as desired.
