In a medium bowl, combine crushed vanilla wafers and melted butter. Press firmly into the bottom and up the sides of a 9-inch pie dish. Refrigerate while preparing filling.
In a large bowl, whisk together instant vanilla pudding mix and cold milk for 2 minutes until thickened.
Add thawed orange juice concentrate and vanilla extract; whisk until smooth.
Fold in the thawed whipped topping until fully incorporated and no streaks remain.
Pour filling into the prepared crust. Smooth the top with a spatula.
Refrigerate for at least 4 hours, or until set. Garnish with orange zest if desired before serving.
Tips
For a stronger orange flavor, add 1 teaspoon orange zest to the filling.
Store leftovers covered in the refrigerator for up to 3 days.
The pie can be frozen for up to 1 month; thaw in the refrigerator before serving.