Preheat the oven to 325°F (160°C) and coat a 9-inch springform pan with non-stick spray.
Stir together the vanilla wafer crumbs and melted butter in a mixing bowl, then firmly press the blend into the base of the prepared pan. Bake the crust for 10 minutes, then remove and let it cool fully.
In a separate bowl, combine the mashed bananas with lemon juice and set aside.
Using a large bowl, beat the cream cheese until its texture is completely smooth. Incorporate the granulated sugar and flour, mixing thoroughly.
Add the eggs individually, mixing after each addition. Blend in the sour cream and vanilla extract.
Gently fold the banana-lemon mixture into the cheesecake batter.
Transfer the batter to the cooled crust, smoothing the top evenly.
Place the cheesecake in the oven and bake for about 1 hour, or until the center appears mostly set.
Remove the cheesecake from the oven and allow it to cool entirely at room temperature.
Meanwhile, whisk the banana pudding mix with the whole milk following the instructions on the package.
Spread the prepared pudding mixture over the cooled cheesecake, then refrigerate for no less than 4 hours, or preferably overnight, to fully set.
Just before serving, garnish the top with whipped cream and a sprinkling of extra vanilla wafer crumbs.