Melt butter in saucepan over medium low heat, add onions, celery and carrots and cook for about 10 minutes, until onions become translucent.
Whisk flour into the onion mixture, cook for 1 minute, then whisk in the hot chicken stock.
Turn the heat up to medium. While stirring, cook 5 minutes until moderately thickened.
Next, whisk in the heavy cream and peanut butter, heat the soup through but do not bring to a boil. Stir in the lime juice.
Serve with optional toppings such as chopped toasted peanuts, scallions, cilantro, cayenne or hot sauce.