Leave ice cream at room temperature about 15 min., or until soft enough to easily press with back of spoon. Working quickly, scoop ice cream into pie shell, pressing and spreading to edges and slightly mounding in the middle. (Don’t worry if the shell crumbles a bit, it will hold together once frozen.) Cover and freeze until solid, minimum 1 hr., or overnight.
Stir icing sugar into berries.
Cut ice cream pie into wedges and plate. Top slices with berry mixture. Garnish with mint sprigs, if desired.
Other pie combos to try: