unflavored gelatin (1 envelope)
few drops green food color
pistachio nuts, chopped
heavy cream, whipped, to top
Thoroughly mix gelatin, 1/2 cup sugar and salt in saucepan.
Beat together egg yolks, lime juice and water; stir into gelatin mixture.
Cook and stir over medium heat just until mixture comes to boiling.
Remove from heat; stir in grated peel.
Add food coloring sparingly to tint pale green.
Chill, stirring occasionally, until the mixture mounds slightly when dropped from a spoon.
Beat egg whites until soft peaks form; gradually add 1/2 cup sugar, beating to stiff peaks.
Fold gelatin mixture into egg whites.
Pile into cooled baked pastry shell.
Spread with more whipped cream; edge with grated lime peel.
Sprinkle chopped pistachio nuts in center.
Garnish with thinly sliced lime placed in whipped cream mounds around edge of pie.