Preheat the oven to 375F.

Spray a 9 inch pie pan with cooking spray.

Place the Oreo cookies in a food processor and pulse until finely ground.

Add in the melted butter and pulse until moistened.

Press the mixture into the bottom and up the sides of the pie pan.

Bake for 10 minutes or until fragrant.

Let cool completely on a wire rack.

In a small saucepan, whisk together the granulated sugar and the eggs.

Cook over medium-low heat, whisking constantly until the mixture reaches 160F and coats the back of a metal spoon.

Remove from heat and stir in the melted chocolate and vanilla until smooth.

Cool to just warm, stirring occasionally.

In a large bowl, beat the butter until light and fluffy, about 2-3 minutes.

Gradually add in the cooled chocolate mixture and beat on high speed for 5 minutes or until light and fluffy.

In a clean bowl, beat the cream until it begins to thicken.

Add the powdered sugar and beat until stiff peaks form.

Fold into the chocolate mixture.

Pour the mixture into the pan, smoothing it evenly.

Chill for 6 hours. (At this point, the pie can be stored for up to 2 days ahead of time.)

Beat the cream, powdered sugar, and vanilla on high speed until stiff peaks form.

Top the pie with whipped cream and garnish with chocolate shaving or dust from cocoa powder.