Combine egg whites (at room temperature) and cream of tartar; beat at medium speed of an electric mixer until foamy. Gradually add 1 cup sugar, 1 tablespoon at a time, beating until stiff peaks form. Spread meringue in a lightly greased 9- inch pie plate. Bake at 300° for 40 minutes or until lightly browned; let cool completely away from drafts.
Beat egg yolks in top of double boiler until thick and lemon colored. Add remaining 1/2 cup sugar, lemon rind, and juice. Cook over boiling water, stirring constantly, for 5 minutes or until thick. Remove from heat, and let mixture cool completely.
Beat 1 cup whipping cream until soft peaks form; fold into lemon mixture. Spoon into meringue pie shell; refrigerate overnight.
To serve, beat remaining 1 cup whipping cream until foamy. Gradually add 1 tablespoon sugar, and continue beating until soft peaks form. Spread whipped cream over filling.