Cook egg yolks, 1 cup sugar, juice from two lemons, grated lemon rind and salt in a double boiler, stirring frequently until it reaches the consistency of thick custard.
Soak gelatine in cold water until dissolved. Add to hot custard and let cool.
Beat the egg whites stiff, but not dry. Beat in 1 cup sugar gradually and then beat again. Fold cooled custard into beaten egg whites. Put into baked pie shell and chill three hours. Serve with whipped cream.
Makes: 4