Preheat oven to 325°F (163°C). Line a 9-inch (23cm) springform pan with parchment paper in the bottom and grease the sides.
Combine the crust ingredients in a small bowl. Press the mixture into the bottom and up the sides of the springform pan.
Bake the crust for 8-10 minutes, then set aside to cool.
Cover the outsides of the pan with aluminum foil so that water from the water bath cannot get in (see how I prepare my pan for a water bath). Set prepared pan aside.
Reduce oven temperature to 300°F (148°C).
In a large bowl, beat the cream cheese, sugar, flour and pudding mix on low speed until well combined and smooth. Mixture will be sticky. Be sure to use low speed to reduce the amount of air added to the batter, which can cause cracks. Scrape down the sides of the bowl.
Add the sour cream and mix on low speed until well combined.
Add the eggs one at a time, mixing slowly to combine after each addition. Scrape down the sides of the bowl as needed to make sure everything is well combined.
Add the mashed banana and vanilla extract and mix on low speed until well combined. Mixture will be a little lumpy
Pour the cheesecake batter into the crust.
Place the springform pan inside another larger pan. Fill the outside pan with enough warm water to go about halfway up the sides of the springform pan. The water should not go above the top edge of the aluminum foil on the springform pan.
Bake for 1 hour 30-45 minutes. The center should be set, but still jiggly.
Turn off the oven and leave the door closed for 30 minutes. The cheesecake will continue to cook, but slowly begin to cool as well.
Crack the door of the oven for 30 minutes to allow the cheesecake to continue to cool slowly.
Remove the cheesecake from the oven and water bath wrapping and refrigerate until cool and firm, 5-6 hours or overnight.
When cooled and ready to serve, remove the cheesecake from the springform pan and place on a serving plate.
To make the whipped cream, add the heavy whipping cream, powdered sugar and vanilla extract to a large mixer bowl and whip on high speed until stiff peaks form.
Place a layer of sliced bananas on top of the cheesecake, then pipe a layer of whipped cream swirls on top.
Finish off the cheesecake with a few more banana slices and vanilla wafers. The fresh banana slices are best when added just before serving.
Cheesecake is best when stored well covered in the fridge for 3-4 days.