Preheat oven to 350 degrees.

Press crushed Oreo cookies into bottom of 10-inch spring-form pan. Bake 5-6 minutes or until set. Do not burn! Cool on wire rack while preparing cake. Reduce oven heat to 300 degrees.

Beat softened cream cheese, sugar and vanilla until smooth and creamy; add eggs one at a time beating well after each addition. Divide batter equally between two bowls.

Melt 1 cup semi-sweet chocolate chips; stir into one of the bowls of cheesecake batter; pour batter into crust prepared pan. Microwave peanut butter until soft, about 20-25 seconds; stir into other bowl of cheesecake batter and pour on top of the chocolate layer.

Bake cheesecake at 300 degrees for 50-60 minutes or until center is almost set (not jiggly). Do not overbake. Don't worry if there are a couple of cracks. They will come together when refrigerated and were covering it in chocolate anyway.

Place pan on cooling rack; cool approximately 1 hour. Carefully run a knife around edge of pan and remove sides of pan. Place cream in a microwave safe bowl and heat for one minute or boiling. Pour chocolate chips into cream and let sit until soft. Stir until chips are melted and mixture is smooth and creamy. Pour chocolate over top and sides of cheesecake. You may want to place your cheesecake on a cookie sheet to catch the run off. Refrigerate overnight; cut optional Reese Peanut Butter cups into quarters and garnish top of cheesecake. Serve with a dallop of whipped cream. It's great to cut the richness. Refrigerate leftovers.