In a mixing bowl, whisk together the vanilla pudding mix and milk until smooth.
Stir in the vanilla extract and let the mixture sit for about 5 minutes until it thickens.
In a separate bowl, fold in the whipped topping until well combined.
Combine the pudding mixture with the whipped topping gently.
In a serving dish, layer vanilla wafers on the bottom.
Add a layer of the pudding mixture over the wafers.
Place a layer of sliced bananas on top of the pudding.
Repeat the layering process until all ingredients are used, finishing with pudding on top.
Cover the dish with plastic wrap and refrigerate for at least 2 hours.
Before serving, garnish with additional banana slices and crushed wafers.