Freeze your butter for about 30 minutes, then grate quickly and return back to the freezer for about 15 more minutes.
While the grated butter is in the freezer, in a medium bowl, whisk together the flour, sugar, and salt.
In a small bowl whisk together the egg yolk, vanilla, and milk and set aside.
Work the cold butter into the flour mixture until it looks like coarse breadcrumbs.
Stir the wet ingredients into the dry - it will be quite coarse.
Working as quickly as possible as not to melt the butter, gently knead the dough a just a few times. It should be crumbly but hold together when squeezed. If you knead too much the crust will be very hard.
Lightly grease the bottom and sides of a tart pan that has a removable bottom.
Roll the dough in the rough shape of your pan and gently transfer it. Press it into the bottom and up the sides - about 1/8” thick. You can also simply press the crust into the pan without rolling.
Prick the bottom of the crust all over with a fork then refrigerate for at least 30 minutes.
While the dough is chilling, preheat the oven to 375°F.
Line the crust with parchment or foil and fill with pie weights or dry rice or beans.
Bake for about 15 minutes. It should be dry.
Remove the weights and parchment (or foil) and return the crust to the oven to bake for another 8 to 10 minutes, until golden brown. The weights will be incredibly hot so take care when transferring them to another container.
Remove the crust from the oven and cool it completely on a rack before filling.
Notes
Use this pastry crust to make all sorts of beautiful fruit or chocolate tarts.