EASY LEMON PIE
You can replace the lemons with limes to make a simple "Key lime pie".
Note: as this recipe, hailing from the U.S.A., is thus obviously directed to palates accustomed to over-sweet pastry products and desserts, to make it less sweet you can either diminish the amount of sugar in the bottom crust mixture, or leave it out altogether.
For the crust, I would not use the Scottish Walkers brand Digestive biscuits, which taste awful, but rather look for Digestives of the brands mentioned below.
300 ml (about 9 - 10 pieces) finely crushed Digestive biscuits (McVitie's, LU)
(2 - 3 tbsp sugar, or to taste)
70 g unsalted butter
4 egg yolks
(2 - 3 tsp grated lemon or lime zest)
400 g sweetened condensed milk
125 ml lemon or lime juice
Lemon or lime zest may be omitted from the filling, but if you want to use it (for added flavour), grate the zest from the fruit before juicing them. Also, use unwaxed, preferably organically grown, citrus fruit.
Halve and juice the fruit and strain the juice. Lightly whisk together the egg yolks and the grated lemon zest, if using it. Whisk in the condensed milk and the measured strained juice. Set aside at room temperature.
Combine the crushed biscuits (and the sugar), add the melted butter. Mix with a fork until well combined. Pour the mixture in a pie pan or springform pan (Ø 20 - 22 cm) and press evenly onto bottom and sides of the pan. Depending on the brand of biscuits used, the mixture may be rather crumbly, resembling moist sand, but keep pressing lightly and patiently and the crust will eventually just about hold its shape. Place the pan in refrigerator for about 20 minutes for the crust to become firm.
Bake the bottom crust at 160 °C until it is lightly browned, for about 15 minutes. Remove from the oven, place on a wire rack and let cool at room temperature for about 20 minutes.
Meanwhile, lower the oven temperature to 140 - 150 °C.
Pour the filling on the crust in the pan and bake for another 15 minutes, or until the filling is set around the edges but still wobbly at the centre.
Let the pie cool on a wire rack, then place in refrigerator for at least 2 to 3 hours, until the filling has set enough to hold its shape when cut.
If you like, serve the pie garnished with whipped cream and pieces of candied lemon (see the pictures above).
Recipe source: adapted from "Key Lime Pie", PBS/America's Test Kitchen, "Diner Pies", 2002.