In a mixing bowl, add the instant pudding and milk and whisk together until thickened, about 2 minutes.
Fold in 2 cups of the whipped topping (about 2/3 of the container) into the pudding until evenly combined.
Arrange the slices of one banana in an even layer around the bottom of the pie crust.
Pour the pudding mixture over the top. Gently spread the remaining whipped topping around the top of the pie. Garnish with remaining banana slices.
Allow to chill in the refrigerator for at least 3 hours before serving.