Preparation

• Add ice cubes and water to a measuring cup. Cut the butter into ¼" cubes. Place both items in the refrigerator until ready to use.
• In a stand mixer bowl, add the flour and salt. Mix using the paddle attachment on the lowest speed for about 10 seconds. Add the chilled butter to the bowl and mix until coarse crumbles.
• Gradually add 1 tablespoon of ice-cold water to the bowl until the dough looks lumpy and hydrated but not wet or sticky.
• Press the dough into a 1" thick round disc and wrap it in plastic. Store in the refrigerator for at least 4 hours or overnight.
• Roll the dough into a 14-inch circle, slightly less than ¼" thick, and place it into a 9-inch pie dish.
• Preheat the oven to 375°F (190°C) and freeze the crust for 20 minutes.
• Bake the crust with weights for 20 minutes, then for an additional 15 minutes until golden brown.
• Prepare the lemon filling by whisking together sugar, cornstarch, water, and egg yolks. Simmer a separate mixture of water, sugar, lemon zest, lemon juice, and salt until it reaches 190°F (87°C).
• Temper the egg mixture by slowly adding the hot lemon mixture and whisking continuously, then combine with remaining lemon mixture and thicken.
• Immediately strain the filling into the cooled pie crust and chill in the refrigerator for about 6 hours.
• Prepare the meringue topping by whipping egg whites, vanilla, and salt until foamy, then slowly adding a sugar syrup until thick and shiny.
• Spread the meringue topping onto the chilled pie and toast with a kitchen torch.