Start by preheating your oven to 325°F (160°C).
In a medium bowl, combine the crushed Nilla Wafer cookies and melted butter. Mix until the crumbs are evenly coated. Press this mixture firmly into the bottom of your springform pan to form a crust. Bake for 10 minutes, then remove it from the oven and allow it to cool.
In a large mixing bowl, beat the cream cheese with an electric mixer until smooth and creamy. Gradually add the granulated sugar and flour, mixing until fully incorporated.
Add the eggs one at a time, mixing well after each addition.
Gently fold in the mashed ripe bananas and vanilla extract or vanilla bean paste.
Stir in the sour cream and salt until the mixture is smooth.
Pour the cheesecake filling over the cooled crust in the springform pan. Bake in the preheated oven for about 50-60 minutes, or until the center is set but still slightly jiggly.
Once baked, turn off the oven and crack the door open. Let the cheesecake cool in the oven for about an hour. After that, refrigerate for at least 4 hours or overnight.