If making the crust from scratch, start here. If using store-bought, skip to step 4):

1. Make the Pie Crust Dough (if making from scratch):

* In a large bowl, whisk together the flour and salt.
* Cut in the cold butter using a pastry cutter or your fingers until the mixture resembles coarse crumbs.
* Gradually add the ice water, mixing until the dough just comes together.
* Form the dough into a disc, wrap, and refrigerate for at least 1 hour.

2. Roll and Chill the Crust:

• Preheat the oven to 400°F (200°C).
• On a lightly floured surface, roll the chilled pie dough into a 13-inch circle.
• Transfer the crust to a 9-inch pie plate.
• Tuck the edges under and crimp.
• Refrigerate for 60 minutes (or freeze for 30 minutes).

3. Blind Bake the Crust:

• Line the chilled crust with parchment paper; fill with baking weights.
• Bake for 16-18 minutes, until edges are lightly golden.
• Remove weights and parchment, brush with heavy cream, prick bottom with a fork.
• Bake until golden brown, 12-14 minutes longer. Cool to room temperature.

4. Make the Lemon Filling:

• In a medium saucepan, whisk together the sugar, cornstarch, flour, and salt.
• Gradually stir in 1 1/2 cups cold water until smooth.
• Cook over medium heat, stirring frequently, until boiling (about 5 minutes).
• Boil for 1 minute, stirring constantly, then remove from heat.

5. Temper the Egg Yolks and Finish the Filling:

• Whisk the egg yolks in a small bowl.
• Slowly add 1/4 cup of the hot sugar mixture to the yolks while whisking (tempering).
• Gradually stir the tempered yolk mixture back into the saucepan.
• Cook over medium heat, stirring constantly, until a thermometer reads 160°F to 180°F (71°C to 82°C).
• Remove from heat; stir in butter, lemon juice, and zest until butter melts.

6. Chill the Filling:

• Pour the hot filling into the cooled pie crust.
• Let cool for 15 minutes.
• Press plastic wrap directly onto the filling’s surface.
• Refrigerate for at least 2 hours.

7. Make the Meringue:

• Place a medium saucepan filled with 1 inch of water over medium heat and bring to a simmer.
• Whisk together the egg whites, vanilla, sugar, salt, and cream of tartar in the bowl of a stand mixer.
• Place the mixing bowl over the simmering water (don’t let it touch the water).
• Continue to mix, scraping the sides frequently, until the sugar dissolves (3-5 minutes, or 160°F/71°C on a thermometer). The mixture should be smooth when rubbed between your fingers.
• Transfer the bowl to the stand mixer fitted with the whisk attachment.
• Whisk on medium-high speed for 4-5 minutes, until glossy and holds medium-stiff peaks.

8. Assemble and Toast the Meringue:

• Dollop the meringue over the chilled pie, completely covering the filling.
• Swirl with the back of a spoon for decoration.
• Toast the meringue with a kitchen torch or under a broiler (about 8 inches from the heat) for 1 minute, until lightly browned.

9. Cool and Serve: * Let the pie cool completely to room temperature before serving. This allows the meringue to set properly.