In a large bowl, beat cream cheese with a hand mixer until creamy. Add the lime juice, evaporated milk and sugar. Beat to combine, about 2 minutes. (Filling should not be lumpy. If it is lumpy, the cream cheese was not soft enough. Simply microwave filling at 30 second intervals and continue to beat until smooth.)
Pour pie filling into crust and smooth out with a spatula. Freeze for 4 to 24 hours.
Take pie out of the freezer about 15 minutes before you serve it. Top with whipped cream and serve.