Preheat your oven to 325°F (163°C). In a mixing bowl, combine the vanilla wafer crumbs, sugar, and melted butter until it resembles wet sand. Press this mixture firmly into the bottom of a lined springform pan to create a solid crust. Bake for 8-10 minutes, then let it cool while you prepare the filling.

Lower the oven temperature to 300°F (148°C). In a large mixing bowl, beat together softened cream cheese, sugar, all-purpose flour, and instant banana cream pudding mix until smooth and creamy. Gradually mix in sour cream, then add eggs one at a time, ensuring each is fully incorporated before adding the next. Finally, fold in the mashed ripe bananas and pure vanilla extract until blended.

Pour the rich batter over the cooled crust in the springform pan. Place the pan inside a larger roasting pan and add warm water halfway up the sides to create a water bath. Bake for 1 hour and 30-45 minutes; the center should be set but still slightly jiggle when moved.

Once baked, turn off the oven and let the cheesecake cool inside for 30 minutes with the door closed. Afterward, crack the oven door and let it cool for another 30 minutes. Finally, refrigerate for at least 5-6 hours or overnight for the best flavor and texture.

In a mixing bowl, whip together the cold heavy whipping cream, powdered sugar, and vanilla extract. Beat until stiff peaks form. Remove the cheesecake from the springform pan and layer the top with sliced bananas. Generously spread the whipped cream over the bananas.

Garnish with additional banana slices and whole vanilla wafers just before serving for a decorative touch.