In the bowl of a stand mixer fitted with the paddle attachment, combine flour and salt on low speed. Gradually add butter until pea size lumps form, about 2 minutes. Gradually add ice water on low speed until dough comes together. Entire amount may not be necessary. Continue mixing for 30 seconds. Shape dough into a flat rectangle. Wrap in plastic wrap and chill for at least 1 hour in the refrigerator. Lightly flour work surface and roll chilled dough into a 16×28 rectangle that is ¼ inch thick. Fold the dough into thirds, as if folding a letter. The turned dough should measure about 9×16. This is the first turn. Place on a parchment lined sheet pan and wrap with plastic. Chill dough in the refrigerator for 15 minutes. For the second turn, position the turned dough so that the seam side is facing you. Roll chilled dough into a 16×28 rectangle that is ¼ inch thick. Fold into thirds as described above and chill another 15 minutes. This is the second turn. Repeat two more times, for a total of four turns. Chill after each turn. After the last turn is complete, roll out the chilled dough into a 16×28 rectangle that is ¼ inch thick. Trim edges and cut the dough in half, to yield 2 14×16 rectangles. Layer the puff pastry sheets, separated by a piece of parchment paper, on a parchment lined sheet pan. Wrap tightly in plastic wrap and freeze for up to 1 week.