Spiderweb Pumpkin Cheesecake

Step 1
Preheat oven to 350 degrees F (175 degrees C).

Step 2
Mix chocolate wafer crumbs and melted butter in a bowl; press onto the bottom of a 9-inch springform pan.

Step 3
Beat cream cheese and sugar with an electric mixer in a large bowl until smooth. Beat in eggs, one at a time, until just blended. Stir in pumpkin pie filling and cornstarch; pour over chocolate wafer crust.

Step 4
Bake in preheated oven until center is just set, 50 to 55 minutes.

Step 5
Spread sour cream over top of warm cheesecake; let cool.

Step 6
Melt chocolate and oil in a microwave-safe bowl in a microwave for 1 minute; stir until completely melted. Drizzle chocolate onto sour cream topping in a spiral pattern, starting from the center; draw a toothpick outward, from center to edges, through circles to form a web. Remove side of pan and serve.