Mix butter and sugar in a medium bowl until creamy, about 2 minutes. Add flour and salt and mix until just incorporated, then add egg yolk and mix until a crumbly dough forms. Gently knead the dough just until it comes together to form a smooth dough. Shape the dough into a disc, wrap in plastic, and chill at least 1 hour.
To roll out the tart shell, remove and discard the plastic surrounding the tart dough. Dust the work surface and the top and bottom of the tart dough disc lightly with flour. Begin rolling the dough, rotating a quarter turn between rolls to keep the dough from sticking and to better keep a uniform circle shape, until the dough is an 11–12-inch round circle and about ⅛-inch thick. If the dough is too tender to roll, press pieces of dough into the tart pan, making sure the bottom and sides are about ⅛-inch thick.
Carefully transfer the dough to a standard 10-inch tart pan and press the dough into the bottom and sides of the pan, trimming off any excess dough. Dock the bottom of the crust using a fork.
Transfer the tart shell to the freezer for at least 30 minutes and preheat the oven to 350°F or to the temperature directed in your recipe.
Remove the tart shell from the freezer and line the inside with parchment paper or tin foil. Fill with pie weights or dried beans (you will not want to use these beans for food at a future date) all the way to the very top of the crust.
Bake the tart filled with pie weights for about 15 minutes. Remove the tart shell from the oven and carefully remove the pie weights and parchment or foil. Return the tart shell to the hot oven to fully bake the bottom of the crust, another 10–15 minutes.