For the pie filling: With an electric mixer, blend the peanut butter and cream cheese until smooth. Add the melted butter to peanut butter mixture, then fold in whipped cream. Pour into the baked pie shell and refrigerate for one hour before serving. If desired, glaze with ganache.
Ganache: In a saucepan over medium heat, bring the cream and butter to a boil. Remove from heat and fold in chocolate until no streaks of white remain. Cool until lukewarm and then glaze cake. Refrigerate an additional one hour before serving.