Preheat oven to 375°F. In a food processor, pulse flour, cold butter, and powdered sugar until mixture resembles coarse crumbs.

Add egg yolk and 2 tablespoons ice water, pulse until dough just comes together. Add more water if needed.

Roll dough on floured surface and cut circles to fit 12 tartlet pans. Press into pans and prick bottoms with fork.

Line shells with parchment and fill with pie weights. Bake for 12 minutes, remove weights and bake 5 more minutes until golden.

For lemon curd, whisk eggs and sugar in a saucepan until smooth. Add lemon juice, zest, and salt.

Cook over medium-low heat, whisking constantly, for 8-10 minutes until mixture coats the back of a spoon.

Remove from heat and whisk in butter one piece at a time until smooth and glossy.

Strain curd through fine mesh sieve to remove any lumps. Fill cooled tartlet shells with warm lemon curd.

Refrigerate for at least 2 hours until set. Dust with powdered sugar before serving.