1. In a medium mixing bowl, add the instant banana cream pudding powder and cold milk.
2. Blend with an electric hand mixer on medium-low speed until it begins to thicken.
3. In a separate large mixing bowl, add the softened cream cheese and beat on medium speed until smooth, scraping down the sides of the bowl as needed.
4. Add the pudding mixture into the fluffy cream cheese and blend until combined.
5. Add the whipped topping and gently stir with a spatula until completely combined.
6. Add in the sliced bananas, mini vanilla wafers, and mini marshmallows, gently stirring until fully coated.
7. For a crunchy texture, serve immediately topped with extra banana slices and wafers. For softer wafers, refrigerate for 30 minutes before serving.