1 9-inch graham cracker crust (page 235), fully baked and cooled, or a store-bought crust
1 1/3 cups heavy cream
1 1/2 cups shredded sweetened coconut
4 large eggs, separated
1 14-ounce can sweetened condensed milk
1/2 cup fresh Key (or regular) lime juice (from about 5 regular limes)
1/4 cup of sugar
Center a rack in the oven and preheat the oven to 350 degrees F. Put the pie plate on a baking sheet lined with parchment of a silicone mat.
Put the cream and 1 cup of the coconut in a small saucepan and bring it to a boil over medium-low heat, stirring almost constantly. Continue to cook and stir until the cream is reduced by half and the mixture is slightly thickened. Scrape the coconut cream into a bowl and set it aside while you prepare the lime filling.
Working with a stand mixer, preferably fitted with a paddle attachment, or with a hand mixer in a large bowl beat the egg yolks at high speed until thick and pale. Reduce the mixer speed to low and beat in the condensed milk. Still on low, add half of the lime juice. When it is incorporated, add the remaining juice, again mixing until it is blended.
Spread the coconut cream in the bottom of the graham cracker crust, and pour over the lime filling. Bake the pie for 12 minutes. Transfer the pie to a cooling rack and cool for 15 minutes, then freeze the pie for at least 1 hour.
To Finish the Pie with Meringue:
Put the 4 egg whites and the sugar in a medium heavy-bottomed saucepan and heat over medium-low heat, whisking all the while, until the whites are hot to the touch. Transfer the whites to a stand mixer, fitted with the whisk attachment, or use a hand mixer in a large bowl, and beat the whites at high speed until they reach room temperature and hold firm peaks.
Using a rubber spatula, fold the remaining 1/2 cup coconut into the meringue. Spread the meringue over the top of the pie, and run the pie under the broiler until the top of the meringue is golden brown. (Or, if you’ve got a blowtorch, you can use it to brown the meringue.)
Return the pie to the freezer for another 30 minutes or for up to 3 hours before serving.
Whip 2 cups of cold heavy cream until soft peaks form. Add 1/4 cup sugar and continue whipping until stiff peaks form. Pile whipped cream over the top of the pie and top with toasted coconut, if desired.