Key Lime Icebox Cake

Combine ¾ cup of granulated sugar, ¼ cup of cornstarch and ⅛ teaspoon of kosher salt in a heavy-bottomed saucepan.

In a bowl, whisk 4 large egg yolks and 2 cups of half-and-half together. Gradually pour this egg mixture into the sugar mixture in the saucepan.

Bring the mixture to a boil over medium heat, while whisking constantly. Boil for 1 minute, while whisking. Remove from heat.

Add 3 tablespoons of butter and 2 tablespoons of Key lime zest. Stir with the whisk until the butter melts.

Whisk in ½ a cup of Key lime juice until it is just blended.

Transfer the custard mixture to a metal bowl. Place the bowl over ice and leave to rest for 8 to 10 minutes, stirring occasionally, until the mixture is cold and thickens slightly.

While the mixture cools, line an 8 inch square baking pan with plastic wrap on the bottom and along the sides. Ensure that 4 inches extend over sides of the pan.

Place 9 graham crackers in the bottom of the pan to form a large square. Spoon ¾ cup of custard over the crackers and spread it out so the cracker layer is covered. Add 9 more crackers and a layer of custard and continue until all the ingredients are used. The top layer should be a layer of crackers.

Pull the overhanging plastic wrap tightly over the cake. Place the pan in the freezer for at least 8 hours.

Remove the cake from the baking pan, and place on a platter; discard plastic wrap. Cover loosely; let stand 1 hour.

Place one cup of whipping cream in a bowl and beat with an electric mixer at high speed until bubbles form on top. Gradually sprinkle in ¼ cup of powdered sugar and continue to beat until soft peaks form.

Spread the whipped cream on top of cake and serve immediately.