1 tbsp. unflavored gelatin
1 c. sugar
1/4 tsp. salt
4 eggs, separated
1/2 c. lime juice
1/4 c. water
1 tsp. lime peel, grated
1 c. heavy cream, whipped
1 (9-inch) pie shell
Few drops green food coloring

Thoroughly mix the gelatin, 1/2 cup sugar, and salt in a saucepan. Beat together the egg yolks, lime juice, and water, stir into the gelatin mixture. Cook over medium heat, stirring constantly, just until the mixture comes to a boil. Remove from the heat, stir in the grated peel. Add the food coloring sparingly to give a pale green color. Chill stirring occasionally, until the mixture mounds slightly when dropped from a spoon.

Beat the egg whites until soft peaks form, gradually add 1/2 cup sugar, beating to stiff peaks. Fold the gelatin mixture into the egg whites, fold in the whipped cream. Pile into the pastry shell. Chill until firm. Spread with additional whipped cream and edge with grated lime.