In a bowl, combine the butter and cookie crumbs until evenly coated. Press the mixture into a 9-inch pie plate. Press it harder. Go back again and press the whole bit harder against the sides and bottom of the plate. Slide it into the oven. Bake for 10 minutes. Go zest and squeeze your limes (not a metaphor). Once the crust is done, take it out and cool it on a rack for 10 minutes.
Filling: In the bowl of your electric mixer, throw in the milk, yolks, and lime juice. Turn on low until its all mixed together. Add the zest and turn on low until you see the flecks throughout the mixture.
Pour the filling into the crust. Bake for 25-30 minutes. You’re looking for a solid center with no wiggle.
Cool the pie down a bit, between another 20-30 minutes. Then throw it in the refrigerator for 2 hours at least.
Serve with unsweetened whipped cream and a slice of lime zest if you’re feeling fancy.