01 - Preheat oven to 350°F.
02 - In a food processor, combine flour, powdered sugar, and salt. Pulse to mix.
03 - Add cold, cubed butter to the flour mixture and pulse until the mixture resembles coarse crumbs.
04 - Add egg yolk and 2 tablespoons cold water. Pulse until the dough just begins to come together, adding an extra tablespoon of water only if necessary.
05 - Turn dough out onto a lightly floured surface, form into a disk, wrap in plastic, and chill for 30 minutes.
06 - Roll dough to 1/8-inch thickness. Transfer to a 9-inch tart pan, pressing to fit. Trim any overhang, prick the base with a fork, and freeze for 10 minutes.
07 - Line crust with parchment, fill with pie weights or dried beans, and bake for 15 minutes. Carefully remove weights and parchment, then bake for an additional 8 to 10 minutes until golden. Allow to cool slightly.
08 - Lower oven temperature to 300°F.
09 - In a mixing bowl, whisk together heavy cream, granulated sugar, eggs, egg yolks, lemon zest, lemon juice, and a pinch of salt until the mixture is completely smooth.
10 - Pour lemon filling into the pre-baked crust. Bake for 20 to 25 minutes, until the edges are set and the center is just slightly jiggly.
11 - Cool tart completely on a wire rack, then chill in the refrigerator for at least 1 hour before slicing.
12 - Dust with powdered sugar and garnish with fresh berries or candied lemon slices as desired.