1. Heat oven to 350 degrees F. Wrap bottom and side of a 9-inch springform pan with foil.Crust
2. Mix together cookie crumbs, sugar and butter. Press over bottom and partially up side of prepared pan. Refrigerate while making filling.Filling
3. In a large bowl, beat cream cheese until smooth. Beat in sugars, cornstarch and pumpkin pie spice until combined. Beat in pie mix, and eggs one at a time; add vanilla and beat until smooth. Reserve 1/2 cup batter.
4. Microwave chocolate for 30 seconds, stir and microwave another 15 seconds. Stir again and mix into reserved batter; microwave an additional 15 seconds.
5. Pour batter into prepared pan. Dollop heaping tablespoons of the chocolate mixture over top of cake and swirl with a small knife or spatula. Place in roasting pan, adding enough hot water to come halfway up side of foil.
6. Bake at 350 degrees F for 70 to 80 minutes, until just set. Run a knife around edge of pan. Cool in pan on rack. Cover; refrigerate overnight. Remove side of pan to serve.