Preheat your oven to 350°F (175°C). In a mixing bowl, combine crushed chocolate cookies with melted unsalted butter, mixing until well-coated. Press into a pie dish and bake for 10 minutes until set. Cool completely.

In another bowl, whisk together creamy peanut butter, powdered sugar, and vanilla extract until smooth. Spread the filling evenly into the cooled crust.

In a small saucepan, combine chocolate chips and heavy cream over low heat. Stir until melted and smooth. Cool slightly, then drizzle over the peanut butter layer.

Swirl the ganache into the filling using a toothpick for a marbled effect. Chill the pie covered for at least 2 hours.

Before serving, garnish with chocolate shavings and chopped peanuts. Slice and serve chilled, optionally with ice cream or whipped cream.