Start by preheating your oven to 325°F (163°C). Line the bottom of a springform pan with parchment paper to prevent sticking. This step ensures the cheesecake releases easily later.
Crush the Nilla wafers in a food processor until they resemble fine crumbs. Mix the crumbs with sugar and melted butter until evenly combined.
Press the mixture firmly into the bottom of the prepared pan. Bake the crust for about 10 minutes and then set it aside to cool slightly.
Add softened cream cheese to a mixing bowl and beat until smooth. This step removes lumps and creates a creamy base.
Mix in mashed bananas and sour cream until everything is fully combined. Then add sugar, banana pudding mix, and vanilla extract.
Lightly beat the eggs in a separate bowl and gently mix them into the batter. Mixing them slowly helps prevent over‑mixing and cracking.
Wrap the outside of the springform pan with several layers of foil. This protects the cheesecake from water entering the pan during baking.
Place the wrapped pan into a larger roasting pan. Pour hot water into the roasting pan until it reaches about an inch deep.
A water bath helps the cheesecake bake slowly and evenly. This technique creates a smooth and creamy texture.
Pour the cheesecake filling into the cooled crust and spread it evenly. Carefully place the roasting pan with the cheesecake into the oven.
Bake the cheesecake for about 70–80 minutes until the edges are set but the center still jiggles slightly. This means the cheesecake is perfectly baked.
Turn off the oven and slightly open the door. Let the cheesecake sit inside the warm oven for one hour.
After cooling in the oven, transfer the cheesecake to a wire rack. Allow it to cool completely at room temperature.
Once cooled, cover the cheesecake and refrigerate it for at least 5 hours or overnight. This chilling time helps the cheesecake firm up properly.
Before serving, carefully remove the cheesecake from the pan and decorate with whipped cream, banana slices, and wafers.