Ingredients
Method
Melt 2 Tbsp. unsalted butter in a large deep skillet over medium-high heat. Cook 2 lb. turkey necks and/or wings, turning occasionally, until deeply browned, 12–15 minutes. Add 2 medium onions, coarsely chopped, 2 medium carrots, peeled, coarsely chopped, and 4 medium celery stalks, coarsely chopped, and cook, stirring occasionally, until vegetables are deeply browned, 12–15 minutes. Pour in 6 cups low-sodium chicken broth and bring to a boil, scraping up any browned bits stuck to bottom of pan with a wooden spoon. Reduce heat to medium-low and simmer, uncovered, stirring occasionally, until liquid is reduced by half, 40–50 minutes.
Strain through a fine-mesh sieve into a heatproof large measuring glass and press on solids to extract any liquid; discard solids. Add more broth if needed to measure 4 cups. Do ahead: Gravy base can be made 2 days ahead. Let cool; cover and chill. Reheat over medium, stirring occasionally, until warmed through.
Mix ½ cup (1 stick) unsalted butter, room temperature, 2 tsp. finely chopped rosemary, 2 tsp. finely chopped sage, 2 tsp. finely chopped tarragon, and 2 tsp. finely chopped thyme in a small bowl to combine. Season with kosher salt and freshly ground pepper. Transfer 2 Tbsp. herb butter to another small bowl and set aside for gravy.
Place a rack in lowest position in oven; preheat to 425°. Rinse one 14–16-lb. turkey inside and out; pat dry with paper towels. Starting at neck end, slide your fingers between skin and breast to loosen skin. Rub 4 Tbsp. herb butter over breast meat under skin. Place turkey on a roasting rack set inside a large roasting pan. Season cavity generously with salt and pepper, then stuff with 4 Tbsp. unsalted butter, room temperature, 5 rosemary sprigs, 5 sage sprigs, 5 tarragon sprigs, and 15 thyme sprigs. Loosely tie legs together with kitchen twine; tuck wing tips under. Rub remaining herb butter over outside of turkey; season generously with salt and pepper.
Roast turkey 20 minutes. Reduce oven temperature to 350° and roast 1 hour, pouring 1 cup low-sodium chicken broth over turkey and adding 1 Tbsp. unsalted butter to pan halfway through. Baste turkey with pan juices, pour another 1 cup low-sodium chicken broth over, and add another 1 Tbsp. unsalted butter to pan. Tent turkey loosely with foil and continue to roast, basting with pan juices and adding 1 cup low-sodium chicken broth and 1 Tbsp. unsalted butter every 45 minutes, until an instant-read thermometer inserted into the thickest part of a thigh registers 175°, 1¾–2 hours longer. Transfer turkey to a platter and let rest 30 minutes.
While the turkey rests, strain pan juices into a medium bowl and whisk in gravy base. Melt reserved 2 Tbsp. herb butter in a large saucepan over medium heat. Sprinkle ¼ cup all-purpose flour and cook, whisking constantly, until roux is golden brown, 5–7 minutes. Whisking constantly, gradually pour in pan juice mixture and bring to a boil. Reduce heat and simmer, whisking often, until gravy is reduced to about 4½ cups, 8–12 minutes. Season with salt and pepper.
Carve turkey and serve with gravy alongside.