Crust:
Preheat your oven to 350°F (175°C).
Mix graham cracker crumbs, sugar, and melted butter in a bowl until combined.
Press the mixture into the bottom of a 9-inch springform pan.
Bake the crust for 8-10 minutes. Remove and let it cool while preparing the filling.

Cheesecake Filling:
In a mixing bowl, beat the cream cheese and sugar until smooth.
Add mashed bananas, eggs, vanilla extract, sour cream, and flour. Mix until well combined and creamy.
Pour the filling over the cooled crust.
Bake the cheesecake for about 55-60 minutes until the edges are set but the center slightly jiggles.
Turn off the oven and let the cheesecake sit inside for an additional hour.
Remove from the oven and let it cool completely before refrigerating for at least 4 hours or overnight.

Topping:
In a bowl, whisk together cold milk and instant vanilla pudding mix until thickened.
Spread the pudding over the cooled cheesecake.
Top with whipped cream or whipped topping.
Garnish with sliced bananas and vanilla wafers before serving.