bring to a boil and cook, scraping up the browned bits from the pan, until the
liquid is reduced, about 3 minutes. Add the 5 cups of
liquid from Step 2. Increase the heat to high and return to a boil, whisking often and scraping up any remaining browned bits. Boil until reduced to 2 3/4 cups, 8 to 12 minutes. Whisk the reserved broth-and-flour mixture into the roasting pan. Boil, whisking constantly, for 2 to 3 minutes.