Prepare the crust: In a mixing bowl, combine graham cracker crumbs, sugar, and melted butter. Stir until the crumbs are well coated and the mixture is crumbly. Press this mixture firmly into the bottom of a pie dish or a tart pan, using the back of a spoon to make an even layer. Chill in the refrigerator while preparing the filling.

1. Make the filling: In a large bowl, whisk together the Greek yogurt, sweetened condensed milk, lime juice, lime zest, and vanilla extract until smooth and well combined.
2. Assemble the pie: Pour the yogurt filling into the chilled graham cracker crust. Smooth the top with a spatula or spoon to ensure it’s even.
3. Chill the pie: Refrigerate the pie for at least 3-4 hours, or until the filling is set and firm to the touch.
4. Serve: Once chilled and set, top the pie with whipped cream (if desired) and additional lime zest or lime slices for decoration. Slice and serve!