One 9-inch pie. A graham crust, four yolks, a can of sweetened condensed milk, and Key lime juice. Baked until just set, then chilled.
Yield: 8 slices · Active time: about 25 minutes · Bake: about 25 minutes total · Chill: at least 3 hours
Ingredients
Graham crust
1½ cups (150 g) graham cracker crumbs, from about 10 full sheets
3 tablespoons granulated sugar
5 tablespoons (70 g) unsalted butter, melted
A pinch of fine salt
Filling
4 large egg yolks
1 can (14 ounces / 397 g) sweetened condensed milk
½ cup plus 2 tablespoons (150 ml) Key lime juice, fresh or bottled
1–2 teaspoons finely grated Key lime zest, if you have fresh limes
For serving: lightly sweetened whipped cream.
Method
Heat the oven to 350°F (175°C).
Stir the crumbs, sugar, melted butter, and salt until the mixture looks like damp sand. Press it firmly into the bottom and up the sides of a 9-inch pie plate. Bake 8 to 10 minutes, until it smells toasty and looks set. Cool on a rack.
Whisk the yolks until they lighten slightly. Whisk in the condensed milk, then the juice and zest, until the filling is smooth and a little thicker than when you started.
Pour the filling into the crust. Bake 15 to 17 minutes, until the edges are set and the center still has a slight jiggle. Do not brown the filling.
Cool to room temperature, then refrigerate at least 3 hours, preferably overnight, before slicing. Top with whipped cream at the table.