11 graham crackers , processed to fine crumbs (1 1/4 cups)
3 tablespoons granulated sugar
5 tablespoons unsalted butter , melted
Whipped Cream Topping
3/4 cup heavy cream
1/4 cup confectioners' sugar
1/2 lime , sliced paper thin and dipped in sugar (optional)
For the Filling: Whisk zest and yolks in medium bowl until tinted light green, about 2 minutes. Beat in milk, then juice; set aside at room temperature to thicken.
For the Crust: Adjust oven rack to center position and heat oven to 325 degrees. Mix crumbs and sugar in medium bowl. Add butter; stir with fork until well blended. Pour mixture into 9-inch pie pan; press crumbs over bottom and up sides of pan to form even crust. Bake until lightly browned and fragrant, about 15 minutes. Transfer pan to wire rack; cool to room temperature, about 20 minutes.
Pour lime filling into crust; bake until center is set, yet wiggly when jiggled, 15 to 17 minutes. Return pie to wire rack; cool to room temperature. Refrigerate until well chilled, at least 3 hours. (Can be covered with lightly oiled or oil-sprayed plastic wrap laid directly on filling and refrigerated up to 1 day.)
For the Whipped Cream: Up to 2 hours before serving, whip cream in medium bowl to very soft peaks. Adding confectioners’ sugar 1 tablespoon at a time, continue whipping to just-stiff peaks. Decoratively pipe whipped cream over filling or spread evenly with rubber spatula. Garnish with optional sugared lime slices and serve.
Some suggestions and tips: In the U.S., one cup = 240 ml, so 3/4 cup is 180 ml. A tablespoon is 15 ml. Powdered sugar is icing sugar. If you prefer, you can use a meringue atop the pie, rather than whipped cream, although the whipped cream is more traditional. Some recipes don't have you bake the filling, but I think baking improves the texture by firming it just enough--otherwise, the filling in KLP is often runny.