Preheat oven to 375°F.

Place the vanilla wafers in a food processor or mini-chopper.  Pulse until finely ground.  (Note: This should produce 1¾ cups of vanilla wafer crumbs.  If needed, process additional vanilla wafers.)

In a medium bowl, mix together 1½ cups of the vanilla wafer crumbs, brown sugar and melted butter.  Cover the remaining ¼ cup of crumbs and set aside to use as a garnish.

Press mixture into the bottom of a 9” pie pan.  (Tip: use a straight-sided glass to help press the crumb mixture evenly into the bottom of the pan.)

Bake at 375°F for 16-18 minutes.  Remove crust from oven and set aside to cool.

In a medium bowl, whisk together the sugar, flour, cornstarch, salt and eggs.  Set mixture aside.

Place the milk in a medium saucepan.  Heat over medium heat until milk begins to boil.

Remove pan from heat and gradually pour the hot milk into the egg mixture, whisking constantly while you pour. 

Once fully combined, transfer the filling back into the saucepan.  Place saucepan over medium heat until mixture begins to boil.  (Note: Stir the mixture constantly at this stage to prevent it from burning.)

As soon as mixture begins to boil, remove it from the heat and stir in the butter and vanilla.

To assemble the pie, pour approximately half of the Cream Filling into the cooled pie crust.

Next, slice the bananas and spread evenly across the pie.  Pour remaining Cream Filling on top of the sliced bananas.

Using an offset spatula, smooth the surface of the pie.  Cover and place in the refrigerator until fully chilled (~3-4 hours).

Finally, whip the heavy cream, powdered sugar and vanilla extract together until stiff peaks form.

Using a pastry bag fitted with a large star tip, pipe the whipped cream around the outside of the pie.  Garnish pie with the ¼ cup of remaining crumbled vanilla wafers.

Serve chilled.