Making Peanut Butter Cup Pie is as easy as following these simple steps:

1. Prepare the Crust: In a mixing bowl, combine chocolate cookie crumbs and melted butter. Mix until well combined. Press the mixture firmly into the bottom and sides of a 9-inch pie dish.

2. Chill the Crust: Place the crust in the refrigerator for about 30 minutes to set.

3. Make the Filling: In a large bowl, combine creamy peanut butter and powdered sugar. Mix until smooth and creamy.

4. Whip the Cream: In a separate bowl, whip the heavy cream and vanilla extract until stiff peaks form.

5. Combine Mixtures: Gently fold the whipped cream into the peanut butter mixture until fully incorporated.

6. Fill the Crust: Spoon the peanut butter filling into the chilled crust, spreading it evenly.

7. Melt the Chocolate: In a microwave-safe bowl, combine semi-sweet chocolate chips and vegetable oil. Microwave in 30-second intervals, stirring in between, until melted and smooth.

8. Top the Pie: Pour the melted chocolate over the peanut butter filling, spreading it evenly to cover.

9. Chill Again: Return the pie to the refrigerator and chill for at least 4 hours or overnight for best results.

10. Serve: Before serving, top with whipped cream and garnish with chopped peanut butter cups if desired.