Preheat oven to 350°F (175°C).

Pulse Oreo cookies in a food processor until finely ground.

Add melted butter to the cookie crumbs and pulse until well combined.

Press the mixture firmly onto the bottom and up the sides of a greased 9-inch pie plate to form the crust.

Bake the crust for 15 minutes.

Remove from oven and cool completely on a wire rack.

In a large bowl, beat cream cheese, Nutella, confectioners' sugar, and vanilla extract until smooth and creamy.

In a separate bowl, beat heavy whipping cream until stiff peaks form.

Gently fold the whipped cream into the cream cheese mixture.

Pour the cream cheese mixture into the cooled Oreo cookie crust.

Refrigerate the pie for at least 30 minutes to set.

In a small saucepan, combine the remaining 1/4 cup heavy whipping cream, light corn syrup, butter, and salt.

Bring the mixture to a boil over medium heat, stirring constantly.

Remove from heat and add finely chopped semisweet chocolate.

Let the chocolate stand for 5 minutes to soften.

Stir the chocolate mixture until smooth and glossy.

Allow the chocolate ganache to cool to a spreadable consistency.

Spread the cooled chocolate ganache evenly over the top of the pie.

Sprinkle the chopped toasted hazelnuts over the chocolate ganache.

Refrigerate the pie for at least 1 hour before serving to allow the ganache to set completely.

Slice and serve chilled.