Line 1 litre mold with wax paper and then with lady finger halves.

Mix lemon juice with sugar and cornstarch in top of double boiler and cook over simmering water until mixture is thickened. Add the butter and stir until melted. Add beaten egg yolks, stirring constantly, and cook 2 minutes longer. Stir in grated zest and then fold in the beaten egg whites, mixing lightly but thoroughly.

Pour half the mixture into lined mold. Cover with layer of lady finger halves. Repeat layers. Refrigerate overnight.

Unmold onto crystal pedestal cake platter. Pipe whipped cream onto top and around bottom edge of cake. Garnish with paper thin slices of candied lemon peel.