01 - Set oven temperature to 350°F (175°C) and allow to preheat.
02 - In a food processor, blend flour, powdered sugar, and salt. Add cold, cubed butter and pulse until a crumbly texture forms.
03 - Add egg yolk with 2 tablespoons cold water to the flour mixture, pulsing just until the dough begins to combine. Add additional water if needed.
04 - Transfer dough to a floured work surface, shape into a disk, wrap, and chill for 30 minutes.
05 - Roll chilled dough to 1/8-inch thickness. Gently fit into a 9-inch tart pan, trim edges, prick base with a fork, and freeze for 10 minutes.
06 - Line crust with parchment paper, fill with pie weights or dried beans, and bake for 15 minutes. Remove weights and continue baking 8 to 10 minutes until golden. Let cool slightly.
07 - Lower 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 smooth.
09 - Pour lemon filling into the slightly cooled crust. Bake for 20 to 25 minutes, until edges are set and center still shows a slight jiggle.
10 - Allow tart to cool completely, then refrigerate for at least 1 hour before serving.
11 - Dust tart with powdered sugar and garnish with berries or candied lemon slices as desired.