This is the recipe we got on our way to Key West, Florida all those years ago - makes 1 nine inch pie

1 can condensed milk
4 egg yolks
1/2 cup lime juice
pre-baked pie shell

Beat 1 egg white until stiff. Fold into the above mixture. Beat 3 egg whites and gradually add 6 tablespoons sugar and 1/2 teaspoon cream of tartar. Put into a baked pie shell and bake until egg whites are golden brown. Bake at 350 degrees.