In a saucepan melt butter. Add flour, brown sugar, and crushed pecans. Stir until combined. Press into a 9½-inch deep pie plate.
Preheat oven to 350°F. Bake 15 to 20 minutes until crust begins to brown. Cool completely.
To make cream cheese layer:
In a medium bowl beat cream cheese until creamy. Add powdered sugar and heavy cream; mix until smooth. Spread over cooled pecan crust. Refrigerate to set.
To make pudding layer:
In a medium bowl whisk egg yolks. Add milk; whisk until combined. Set aside. In a separate medium bowl whisk sugar, cocoa powder, cornstarch, flour, and salt until combined.
In a saucepan over medium heat combine egg yolk mixture and flour mixture. Whisk constantly until pudding begins to thicken and bubble. Add butter and vanilla, stirring until butter is melted. Pour chocolate pudding in a shallow bowl. Cover with plastic wrap touching pudding to keep it from forming skin. Refrigerate 30 minutes.
Pour pudding over cream cheese layer. Cover with plastic wrap. Refrigerate overnight.
To make whipped cream topping:
In a stand mixer bowl add heavy cream, powdered sugar, and vanilla. Whip until stiff peaks form. Spread whipped cream over pudding layer.
Drizzle pie with chocolate syrup and sprinkle with chopped pecans. Makes 8 to 10 servings.