Process flour and salt in a food processor. Scatter butter over flour; pulse until mixture resembles cornmeal, 7–12 pulses. Transfer mixture to a medium bowl.
Drizzle 3 tablespoons ice water over flour mixture. Using a rubber spatula, mix dough together, pressing against sides of bowl, until a rough dough comes together. If it's still too dry, drizzle in additional water, by tablespoon, just until it comes together.
Dump shaggy dough out onto a large piece of plastic wrap. Form dough into a 4-inch disk, then wrap tightly in plastic and refrigerate at least 30 minutes (or up to 3 days).
Generously flour a work surface. Unwrap dough and lightly dust with flour. Roll dough out into an ⅛-inch thick 13-inch round.If dough is too firm, let it sit at room temperature for about 5 minutes before rolling out. Fold dough in quarters; place corner in center of a 9-inch pie plate. Gently unfold dough to cover plate, using one hand to pick up edges of dough and an index finger to press dough into corners and up sides. Trim dough overhang to ½-inch then tuck edges under and crimp using thumbs and pointer fingers. (*see note on crimping.) Dough edges should be somewhat one top of pan edges (to avoid shrinking during baking).
Refrigerate dough-lined pie plate for 20 minutes. Prick bottom, sides and corners with a fork. Line dough with a piece of foil, pressing it firmly into corners and sides, and folding over rim. Prick foil about a dozen places with a fork. Refrigerate shell for at least 1 hour or up to 2 days.
Heat oven to 400ºF (204C) with rack set in lowest position.
Place pie plate on a baking sheet. Bake shell until edges are set and starting to brown, pressing down on foil with an oven mitt to deflate when it starts to puff up (this happens for me around 8 or 10 minutes—continue deflating every minute or so after that) 15–20 minutes total.
Remove foil and continue to bake just until shell is light golden brown, about 10 more minutes.