With a fluffy texture and a pure flavor, this pie is typical of the lofty “mile high” pies that were popular decades ago, when electric mixers were becoming basic equipment in most home kitchens. Electricity rescued the cook from the labor of whipping all those egg whites by hand and gave rise to some of the lightest, airiest pies ever made. See page 137 for a genuine Mile High Strawberry Pie.
Makes one 9-inch pie
Basic All-American Pie Dough (page 20) or Crumb Crust for a 9-inch pie shell, made with gingersnaps (page 32)
1 tablespoon (about 1¼ envelopes) unflavored gelatin
⅓ cup water
1¼ cups sugar
⅔ cup fresh lemon juice
5 egg yolks
2 tablespoons freshly grated lemon zest
5 egg whites
¼ teaspoon salt
If you are using pie dough, preheat the oven to 425°F. Roll out the dough and fit it into a 9-inch pie pan, then trim and flute the edges. Bake the pie shell fully, following the instructions on page 22.
If you are using a crumb crust, form and bake the crust as directed in the recipe. Cool either crust completely before filling.
In a medium size, heavy-bottomed saucepan, sprinkle the gelatin over the water. Let stand for a few minutes to soften the gelatin. Add ¾ cup of the sugar and the lemon juice and whisk until blended. Add the egg yolks and whisk again until smooth. Cook over medium heat, whisking constantly. After 3 to 4 minutes, the mixture will become foamy and will nearly double in volume. After 3 to 5 minutes more cooking, the mixture will thicken slightly and you will see wisps of steam rising. Do not let it boil. Remove from the heat and immediately pour the steaming mixture into a large bowl. Stir in the lemon zest.
Refrigerate, whisking every 7 to 10 minutes, until the mixture has cooled and thickened slightly; it will feel tepid, not chilled, to your finger, and a spoonful of it lifted and dropped back onto the surface will leave a small mound. This will take 40 minutes to 1 hour, depending on the size of the bowl and the depth of the mixture in it. At this point, proceed quickly to the egg whites.
Put the egg whites in a large bowl and add the salt. Beat until the whites stand in very soft peaks (a hand-held electric mixer is useful for this), then gradually add the remaining ½ cup sugar and continue beating until the whites stand in fluffy peaks that droop slightly when the beater is lifted. If you are in doubt, it is better to underbeat than overbeat. Stir a big spoonful of the beaten whites into the lemon mixture, then pour the lemon mixture over the whites and, using a rubber spatula or large wooden spoon, fold together gently until there are no drifts of unblended white. Pile the mixture into the prepared pie crust, mounding it in the center. Refrigerate for several hours before serving.