Preheat oven to 350 degrees. Spray a 8×8 springform pie pan with non-stick cooking spray. Set aside.
To make the crust, place vanilla wafers, melted butter, and sweetener in a food processor, and pulse until mixture resembles wet coarse sand. (If you don't have a food processor, blend cookies in a blender, until they resemble coarse sand, and place in a bowl with butter and sweetener. Mix until well combined.) Press crust into prepared pan to form crust. Bake for 10 minutes, and remove from the oven. Let cool to room temperature.
To make the pie filling, combine all of the ingredients together in a blender, (except for the whipped topping), and blend until bananas are smooth. Pour mixture into a large bowl, and fold in 2 cups whipped topping until well blended.
Pour pie mixture over crust and top with remaining whipped topping. drizzle with low sugar caramel syrup, or melted peanut butter, and chopped peanuts if desired. Chill for at least 4-6 hours, (or overnight). Let sit at room temperature for at least 15 minutes to soften. Cut into 12 servings and enjoy!