Gather the ingredients.
Place flour in a medium bowl. Pour 2 to 3 tablespoons of water into the flour and whisk until combined and thick, but not pasty.
Stir flour mixture and remaining water (or stock) into a roasting pan with drippings from roast chicken; whisk to combine and turn heat to medium. Cook, stirring constantly, until gravy is thickened and bubbly, adding more water (or stock) if needed. Season with salt and pepper.
