This dessert is very simple and quick to make and keeps in the freezer for over a week – it's a great dessert to make ahead for a dinner party.
16 whole graham crackers
1/4 cup sugar
6 tablespoons melted butter
2 (14-ounce) cans sweetened condensed milk
1 1/4 cups fresh lemon juice, strained (about 8 lemons)
Grated zest of 2 lemons
8 large egg yolks
2 cups heavy cream
1/2 teaspoon vanilla extract
1/4 cup confectioners' sugar
Heat the oven to 325°F.
To make the crust:
In the bowl of a food processor, break up the graham crackers roughly. Add the sugar. Pulse 8-10 times, or until the cracker crumbs are fine (but don’t overprocess to powder). Pour in the butter and pulse about 10-12 times, or until the butter is blended in and the crumb mixture holds its shape when you squeeze it.
Transfer the mixture to a 9-inch springform pan. Using your fingers, lightly scatter the mixture evenly over bottom of pan. Press crumb mixture into the bottom and two-thirds of the way up the sides of the pan. Use the bottom of a measuring cup to press the crust into place. Set aside.
To make the filling:
In a mixing bowl, whisk the condensed milk with the lemon juice and set aside.
In mixing bowl of mixer using whisk attachment, beat the egg yolks with the lemon zest until pale, about 30 - 45 seconds, and then whisk in the lemon juice-condensed milk mixture.
Place the springform pan on a rimmed baking sheet. Pour the mixture into the crust and carefully transfer the baking sheet to the oven. Bake at 325°F until the center is set, like a soft-setting custard and jiggles slightly, about 25 minutes.
Remove from the oven and cool for 1 hour on a cooling rack. When cooled, loosely cover the pan with foil and freeze for at least 6 hours or overnight.
Pour the heavy cream into the bowl of a stand mixer. Add the vanilla and sift in the confectioners' sugar. Using whisk attachment, whip on low speed to combine and then increase the speed to medium-high and whip until medium-stiff peaks form, about 1 1/2 minutes.
About 15 minutes before serving, wrap a wet, warm kitchen towel around the edges of the springform pan to release the pie from the pan's sides. Unclasp the springform pan and remove the pie.
Fill a pan or pitcher with very hot water, dip your knife in, wipe off the blade, and slice the pie. Place a dollop of whipped cream on top and serve immediately, or keep in the freezer for up to 1 week.