For the Tart Crust:

1. Blend all the ingredients for the pastry dough together and form into a disk.
2. Wrap with a sheet of plastic wrap and chill in the fridge for 30 minutes.
3. Preheat oven to 350 F° (180 C°).
4. Roll the chilled dough out to about ¼-inch thick. Fit into a 9-inch tart pan and score the bottom with a fork.
5. Place a sheet of parchment paper on top of the crust and cover with pie weights (or uncooked rice).
6. Blind bake for 20 minutes or until golden brown. Remove and let cool completely.

For the Lemon Curd:

1. Whisk together egg yolks, sugar, and cornstarch in a medium saucepan over medium heat. Add lemon zest and juice, whisking constantly until thickened. Strain through a mesh strainer.
2. Pour the curd into the baked tart shell and let cool to room temperature before transferring to the refrigerator to set until ready to top with meringue.

For the Italian Meringue:

1. Whip egg whites and cream of tartar until soft peaks form, using either your stand mixer or a hand mixer with the whisk attachment.
2. In a small saucepan over medium heat, whisk sugar and water to make a simple syrup.
3. Once it has come to a boil and thickened slightly, SLOWLY pour the hot syrup into the partially beaten egg whites, while the mixer is on medium-high speed. Keep beating until glossy stiff peaks form.
4. Spoon or pipe the meringue on top of the tart. Using a blow torch, lightly toast the tips of the meringue. Serve and enjoy!