Lemon Parfait

Directions

1. 1
   In a small heavy stainless steel or enameled saucepan combine the lemon juice, the grated lemon rind, the egg yolks and 1/2 cup of granulated sugar.
2. 2
   Beat the mixture until it is well combined and cook it over moderate heat, stirring constantly until it thickens.
3. 3
   Do not let the mixture boil.
4. 4
   Transfer the mixture to a large bowl and let it cool.
5. 5
   In a bowl beat the egg whites with the cream of tartar and a pinch of salt until they hold soft peaks.
6. 6
   Add the remaining 1/2 cup sugar, 1 to 2 tablespoons at a time, beating and beat the meringue until it holds stiff peaks. Fold the meringue into the lemon mixture.