Preheat oven to 180ºC . In a small bowl, combine crumbs and butter;mix well. Press firmly into bottom of a 23 cm springform pan. Bake 10 Minutes. In a medium bowl, combine cream cheese, sugar, vanilla and salt.
Beat with electric mixer on medium speed until smooth.
Add choclate and beat 2 minutes. Fold in whipped cream. Stir in pecans. Turn into baked crust, spreading evenly. Freeze eight hours or longer, until firm. Cover tightly and store in freezer. Remove from freezer half hour before serving for ease in cutting.