1. Preheat oven to 325 degrees. Line 13x9 inch pan with foil, with ends of foil extending over sides of pan.
2. Remove 1/2 cup pecans and set aside. Finely chop remaining pecans. Mix wafter crumbs, chopped pecans and butter. Press firmly onto bottom of prepared pan. Refrigerate until ready to use.
3. Beat cream cheese and sugar in large bowl with electric mixer on medium speed until well blended. Add sour cream, flour and vanilla; mix well. Add eggs, one at a time, mixing on low speed after each addition just until blended. Pour over crust.
4. Bake 45 minutes or until center is almost set. Cool completely.
5. Place caramels in microwavable bowl. Add water. Microwave on HIGH 1 minute or until caramels are completely melted when stirred. Pour over cheesecake; top with reserved pecans.
6. Melt chocolate as directed on package. Drizzle over cheesecake.
7. Refrigerate at least four hours. Use foil handles to remove cheesecake from pan before cutting into pieces to serve. Store any leftovers in tightly covered container in refrigerator.
