Preheat the oven to 375°. Toast the coconut on a baking sheet for 8 to 10 minutes, stirring occasionally, until golden. Transfer the toasted coconut to a bowl and let cool slightly. Add the butter and stir until incorporated. Press the coconut evenly over the bottom and up the sides of a 9-inch pie pan. Cover and freeze until firm, about 15 minutes.
Spoon the ice cream into the coconut shell, mounding it slightly in the center and spreading it out to the edges of the shell; be careful not to dislodge any of the coconut. Cover and freeze for at least 45 minutes, or until ready to serve.
The pie can be frozen for 2 days.