In the work bowl of a food processor, pulse together flour and salt until combined. Add frozen butter, and pulse until butter is dime-size. With processor running, gradually add ⅔ cup (160 grams) cold ice water just until mixture forms a ball. Turn out dough onto a lightly floured surface, and shape into a rectangle. Wrap in plastic wrap, and refrigerate for at least 30 minutes.
Roll dough into a 20x10-inch rectangle. Fold dough in thirds, like a letter. Turn dough 90 degrees; repeat procedure twice. Divide dough in half (about 454 grams each), and wrap each half tightly in plastic wrap. Refrigerate for at least 20 minutes or freeze for up to 3 months.
Recipe by Bake from Scratch at https://bakefromscratch.com/berry-palmiers/