This is one of my all-time favorite desserts, so my standards are high. In my mind, there are two factors that are important in executing the perfect Key lime pie. First is to have the correct balance of sweet to tart flavor. I like my pie a little on the tart side, but not puckery, and to temper its acidity, I top it with a sweetened whipped cream (which I prefer to spongy meringue). The second factor is to make a filling with a silky texture, as opposed to one that is yolky and dense. To ensure the perfect texture, I fold a hand-whipped egg white into the filling before baking. The result is a Key lime pie with a perfectly balanced, luxurious filling and cloud of chiffony cream on top, the ultimate South Florida dessert.
Makes one 9-inch pie, serving 8
- Graham Cracker Crust:
- 1 ½ cups (180 grams) graham cracker crumbs (about 12 whole graham crackers)
- 2 tablespoons (25 grams) granulated sugar
6 tablespoons (85 grams) unsalted butter, melted
Key Lime Filling:
- 4 large (74 grams) egg yolks
- 1 ¼ cups (397 grams) sweetened condensed milk
- 2/3 cup (161 grams) strained Key lime or Persian lime juice
- 2 teaspoons finely grated lime zest
- 1 large (30 grams) egg white
- 1/8 teaspoon cream of tartar
- 1 ¼ cups (290 grams) heavy cream
- ½ teaspoon vanilla paste or extract
- ¼ cup (29 grams) confectioners’ sugar
- ½ teaspoon finely grated lime zest
Make the crust:
- Preheat the oven to 350°F. In a medium bowl, combine the graham cracker crumbs and sugar until well blended. Add the melted butter and stir until blended. Pat the mixture into the bottom and up the sides of a 9-inch pie pan. Bake the crust for about 10 to 12 minutes, until lightly browned. Set the pan on a wire rack and cool the crust completely. Reduce the oven temperature to 325°F.
Make the filling:
- In a medium bowl, whisk the egg yolks until smooth. Add the sweetened condensed milk, lime juice and zest and mix until blended.
- In a medium bowl, using a hand whisk or hand-held electric mixer, beat the egg white until foamy. Add the cream of tartar and whip until the white is shiny and stiff peaks form. Gently fold the meringue into the yolk mixture. Scrape the filling into the cooled crust. Place the pie on a baking sheet and bake for 13 to 16 minutes, until the filling is just set. Place the pie pan on a wire rack and cool completely.
- Refrigerate the pie for at least 2 hours before making the topping.
Make the topping:
- In the bowl of an electric mixer fitted with the whisk attachment, whip the cream with the vanilla at high speed until soft mounds begin to form. Add the confectioners’ sugar and whip at high speed until firm peaks form. Put the whipped cream in a pastry bag fitted with a large open star tip (Ateco #8). Pipe large rosettes of cream around the edge of the pie. Sprinkle the lime zest on top of the rosettes and refrigerate the pie until ready to serve.