Preheat oven 350 degrees.

In a medium mixing bowl, combine the vanilla wafer crumbs and sugar. Add the butter and mix well. Press firmly onto the bottom and up the sides of a 9 inch pie plate. Bake 10 to 12 minutes or until golden brown. Remove from oven, and cool completely before adding filling (about 1 hour).

In a medium, heavy-bottomed saucepan, combine sugar, cornstarch, and salt. Whisk in egg yolks, Gradually add milk and cream. Cook over medium heat, bringing to a gentle boil, whisking constantly until mixture thickens 8-10 minutes. Continue to gently simmer for 1 minute, lowering heat as necessary, and stirring constantly. Remove from heat. Whisk in vanilla, butter, and brandy.

Pour filling into a bowl. Place plastic wrap directly on the surface of the filling to prevent a skin from forming. Cool for about 30 minutes or until filling is warm, but no longer hot.

Pour half of the warm filling into the cooled crust. Peel and slice the bananas into 1/2 inch slices and layer on top of the filling. Pour the remainder of the filling over sliced bananas. Place a clean sheet of plastic wrap directly on the top surface of the filling. Refrigerate pie until completely chilled, at least 3 hours.

Whip the heavy cream in a chilled bowl until soft peaks form. Add powdered sugar and vanilla; continue to whip until peaks are just stiff. Spread whipped cream over topping and shape decoratively into a mound. Refrigerate until ready to serve.