Preheat the oven to 325°F (163°C).

Line the bottom of a 9-inch springform pan with parchment paper. Set aside.

Crush the Nilla wafers in a food processor until resembling fine crumbs, or crush in a ziplock bag with a rolling pin.

Combine the crushed Nilla wafer crumbs and granulated sugar in a mixing bowl and stir until well combined. Add melted butter and mix until moistened.

Scoop the mixture into the prepared springform pan and press it down into an even layer.

Bake for 10 minutes, then set aside to cool while making the filling.

In a large pot, bring water to a boil for the water bath.

Beat the cream cheese in a stand mixer on low-medium speed until smooth (1-2 minutes).

Add the mashed banana and sour cream and mix until combined. Add the granulated sugar, banana cream pudding mix, and vanilla extract, mixing well (30-60 seconds).

Lightly beat the eggs in a separate bowl and add to the mixture, mixing on low speed until just combined. Use a rubber spatula to ensure everything is mixed.

Secure the bottom of the springform pan with aluminum foil to prevent water from entering and place it in an oven bag.

Pour the cheesecake filling into the pan and smooth it out.

Add boiling water to a roasting pan until about 1-inch deep, then carefully place the springform pan in the roasting pan.

Bake for 70 to 80 minutes until edges are set and the center is slightly jiggly. Turn off oven, crack the door, and let cool for 1 hour.

After 1 hour, cool the cheesecake on a wire rack. Once cooled, cover and refrigerate to chill for 5 to 6 hours or overnight.

Run a thin knife around the outside of the cheesecake to loosen it, carefully release the springform pan.

Decorate with whipped cream, sliced bananas, and Nilla wafers.