Heat oven to 325°F.
Combine all crust ingredients in bowl. Press onto bottom and 1-inch up sides of ungreased 9-inch springform pan. Bake 10-12 minutes or until golden brown. Cool.
Combine cream cheese and sugar in bowl. Beat at medium speed, scraping bowl often, until creamy. Gradually add 1 egg at a time, beating well after each addition. Add 1/2 cup sour cream and 2 teaspoons vanilla. Beat at low speed until well mixed.
Pour cream cheese mixture into baked crust. Bake 80-95 minutes or until set 2 inches from edge of pan.
Combine remaining sour cream, 2 tablespoons sugar and 1 teaspoon vanilla in bowl. Evenly spread over top of hot cheesecake. Continue baking 7 minutes. Loosen sides of cheesecake from pan by running knife around inside of pan; remove sides of pan. Cool 2 hours or until completely cooled. Store refrigerated.
Chocolate Cheesecake: Add 1 1/2 cups real milk chocolate chips, melted and cooled, to cheesecake with sour cream and vanilla. Bake as directed above.
A large crack will form around cheesecake. Cheesecake will settle when cooled.