Lightly grease and line the bottom and sides of a 9-inch spring form pan.
Line with parchment paper; very lightly grease the parchment paper as well.
In a medium bowl. mix together the crumbs, butter and sugar.
Press the crumb mixture into the bottom and 3/4 of the way up the sides of the prepared pan; set aside.
In another medium bowl. whip the whipping cream, confectioners' sugar and vanilla extract to firm peaks.
Slowly beat in the condensed milk.
Add mascarpone cheese and peanut butter; beat until thoroughly combined.
Pour into the prepared crust and freeze for several hours; overnight preferred.