Spray a 9-inch pie pan with non-stick cooking spray. Crush Oreo cookies into fine crumbs using a food processor or rolling pin. Combine the cookie crumbs with melted butter and press into the pie pan. Chill for 30 minutes to set.

In a mixing bowl, beat together cream cheese, sugar, and cocoa powder until smooth. Gradually mix in the vanilla, sour cream, and chocolate until combined. Set aside.

In another bowl, beat cream cheese and sugar until smooth. Add peanut butter and mix. Blend in vanilla and sour cream until light and fluffy.

In a separate chilled bowl, whip heavy cream with powdered sugar until stiff peaks form.

Gently fold half of the whipped cream into the chocolate filling and the rest into the peanut butter mixture.

Layer the chocolate filling over the Oreo crust, then the peanut butter filling. Drizzle melted peanut butter on top and swirl.

Cover with foil and refrigerate for at least 6 hours, ideally overnight.

Once set, decorate with chopped peanut butter cups and serve chilled.