In a food processor, pulse flour and salt to combine. Add cold butter and pulse until mixture resembles coarse meal, with a few pea-size pieces of butter remaining. Sprinkle with ice water. Pulse until dough is crumbly but holds together when squeezed (if necessary, add up to 3 tablespoons more water, 1 tablespoon at a time). Do not overmix. Form dough into a 1-inch-thick disk, wrap tightly in plastic, and refrigerate until firm, at least 1 hour (or up to 3 days).