Add the flour, powdered sugar, and salt to the food processor and pulse a few times to combine.
Add the butter and process in long pulses until the butter is in small pieces, around the size of a lemon seed.
In a small bowl, beat the egg yolk, vanilla and 4 teaspoons of cold water with a fork until smooth. Drizzle the egg mixture over the flour mixture making sure to get all of the egg mixture out. Use a spatula to get all of the egg mixture out.
Process the dough with long pulses until a ball of dough forms around the blades and no floury spots remain. Scrape the dough out of the food processor and onto a sheet of cling film.
Pat the dough into a disc, wrap in plastic and chill for at least 30 minutes and up to 3 days.
Unwrap the dough and divide it in half using a bench scraper or knife. Cut one half into six strips and roll the strips out using your hands. Press the strips of dough into the side of your tart pan, pressing into place so the inside circumference of your tart pan is lined with dough. The dough should extend a little bit above the top of the pan.
Take the other half off the dough and press it into the bottom of the pan, making sure that the layer of dough is even. Where the bottom meets the sides, press the dough together to seal.
Freeze the lined pan until the dough is completely firm, 15-20 min. Take the pan out of the freezer and using a paring knife, trim the excess dough off of the top of the tart pan so the dough doesn't extend above the tart pan, Hold onto the excess dough that was removed, it'll come in handy later to patch any cracks you might get during baking.
Using a fork, prick all over the bottom of the tart pan. Press a layer of tin foil directly onto the surface of the dough and into the sides. This serves the same function as pie weights for blind baking.
Bake for 15-20 minutes or until the edge of the crust is golden brown. Remove the tin foil and bake for another 15 minutes so that the crust is parbaked. Patch any cracks in the crust with the reserved raw dough from earlier.