Preheat oven to 160ºC . Mix wafers and butter together.
Press into bottom of springform pan. Bake for 10 minutes. Mix softened cream cheese, quarter cup of sugar and vanilla. Add 2 beaten egg yolks and melted chocolate bits. Beat egg whites until stiff peaks form. Gradually add remaining sugar. Add to chocolate mixture. Whip heavy cream and fold into mixture. Pour over crumb crush and freeze. decorate with additional whipped cream, if desired.
From Connecticut Cooks Favortie Recipes from the Nutmeg State.