Chocolate cheesecake - country living holidays

    
1/2eachocolate wafers (8 oz package)
1tbbutter, softened
4eacream cheese, (8 oz packages) softened
1/2csugar
2tbcornstarch
4lgeggs
1tbvanilla
3easemisweet chocolate squares (1 oz), melted & cooled
8ozsour cream
Directions:
Heat oven to 300. Crush chocolate wafers in food processor or in plastic bag with rolling pin. Add butter and process or knead into crumbs. Pat into bottom of an oiled 9-inch spring-form pan. Bake 10 minutes.In the large bowl of an electric mixer, beat cream cheese until fluffy. Stir together sugar and cornstarch. Beat into cream cheese mixture.Add eggs to mixture one at a time, beating after each addition. Fold in vanilla, chocolate, and sour cream until uniformly combined.Turn cheesecake mixture into hot, crumb-lined pan. Carefully return to oven. Bake until center of cake seems to be almost set when the pan is gently tapped-about 1 hour. Turn off oven and allow cake to sit in oven 1 hour longer.Remove pan from oven; cool to room temperature. Cover without touching surface of cake. Place in refrigerator overnight.To serve, loosen cake from side of pan with a spatula. Remove side of pan. Place cake on serving platter. Decorate with whipped cream, if desired.