Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   1      tablespoon    unflavored gelatin -- (1 env.)
     1/2  cup           sugar
     1/4  teaspoon      salt
   4                    egg yolks
     1/2  cup           lime juice
     1/4  cup           water
   1      teaspoon      grated lime peel
                        few drops green food color
   4                    egg whites
     1/2  cup           sugar
   1      cup           heavy cream -- whipped
   1      9 in          baked pastry shell
                        pistachio nuts -- chopped
                        lime slices for garnish
                        heavy cream -- whipped, to top

Preparation:

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 till 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 till soft peaks form; gradually add 1/2 c sugar, beating to stiff peaks. Fold gelatin mixture into egg whites. Fold in whipped cream. Pile into cooled baked pastry shell. Chill till firm. 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.