Ingredients

  • 1 large egg whites
  • 1 1/4 cups graham wafer crumbs about 12 wafers
  • 1 1/2 tablespoons butter, unsalted melted
  • 1 1/2 tablespoons canola oil
  • 14 ounces milk, low fat, sweetened, condensed or nonfat
  • 23 cup yogurt, low-fat plain
  • 2 teaspoons lime zest freshly grated, prefer key lime
  • 1/2 cup key lime juice if you can't find key lime, regular lime works well
  • 2 tablespoons water
  • 1 1/2 teaspoons gelatin, unflavored
  • 2 tablespoons egg whites, powdered reconstituted according to package directions
  • 1/4 teaspoon cream of tartar
  • 1/2 cup sugar
  • 1 teaspoon vanilla extract
  • 1 x limes slices, for garnish

Method

  • For the crust:
  • Preheat oven to 350F.
  • Coat a 9-inch pie pan with cooking spray.
  • Place egg white, graham cracker crumbs, butter and oil in a medium bowl.
  • Blend with your fingertips until thoroughly combined.
  • Press the mixture in an even layer on the bottom and sides of the pie plate.
  • Bake until lightly browned, about 10 minutes.
  • Cool on a wire rack.
  • For the filling:
  • Whisk condensed milk, yogurt, lime zest and juice in a medium bowl.
  • Stir water and gelatin in a small heatproof cup or bowl.
  • Microwave, uncovered, on High until the gelatin has completely dissolved but the liquid is not boiling, 20 to 30 seconds.
  • (Alternatively, bring 1/2 inch water to a gentle simmer in a small skillet.
  • Set the bowl with the gelatin mixture in the simmering water until the gelatin has dissolved completely.)
  • Stir the gelatin mixture, then whisk into the lime mixture.
  • Set that bowl over a larger bowl of ice water, stirring occasionally, until it begins to thicken, 15 to 20 minutes.
  • Scrape the filling into the pie shell and refrigerate until chilled and set, at least 4 hours and up to 1 day.
  • For the meringue and pie:
  • Position oven rack about 6 inches below the broiler; preheat broiler.
  • Beat reconstituted egg whites and cream of tartar in a mixing bowl with an electric mixer on medium until soft peaks form.
  • Gradually add sugar and continue mixing until the egg whites are glossy and hold stiff peaks.
  • Blend in vanilla.
  • Spread the meringue over the top of the pie, sealing to the edge of the crust and decoratively swirling on top.
  • Broil (leaving the oven door ajar and watching very carefully to prevent burning) until the meringue is lightly browned on top, 30 seconds to 1 minute.
  • Serve garnished with lime slices.