01 - Preheat oven to 350°F (175°C).
02 - In a food processor, combine flour, powdered sugar, and salt. Add cold, cubed butter and pulse until the mixture resembles coarse crumbs.
03 - Add egg yolk and 2 tablespoons cold water. Pulse until the dough just begins to clump together, adding more water if needed.
04 - Transfer dough to a lightly floured surface. Form into a disk, wrap tightly, and refrigerate for 30 minutes.
05 - Roll dough to 1/8-inch thickness. Gently press into a 9-inch tart pan, trim excess, prick base with a fork, and freeze for 10 minutes.
06 - Line the chilled crust with parchment paper and fill with pie weights or dried beans. Bake for 15 minutes, remove weights, then bake an additional 8 to 10 minutes until golden. Cool slightly.
07 - Reduce oven temperature to 300°F (150°C).
08 - In a mixing bowl, whisk together heavy cream, granulated sugar, eggs, egg yolks, lemon zest, lemon juice, and a pinch of salt until completely smooth.
09 - Pour filling into the baked crust. Bake for 20 to 25 minutes, until the edges are set but the center remains slightly jiggly.
10 - Allow tart to cool completely at room temperature, then refrigerate for at least 1 hour before slicing.
11 - Dust with powdered sugar and garnish with fresh berries or candied lemon slices as desired.