Rinse the turkey well inside and out under cold running cold water. Set on a rack set over a rimmed baking sheet. Remove any excess fat or pin feathers and pat dry with paper towels.
In a small bowl, add kosher salt and baking powder and stir to combine. Sprinkle the salt mixture over the bird. Coat well, stopping before a crust forms (you may not need all of the salt mixture).
Transfer the turkey to a rimmed baking sheet and refrigerate, uncovered, for 12 to 24 hours (or loosely cover and refrigerate for up to 3 days).
Remove the turkey from the refrigerator and let sit at room temperature 2 hours prior to roasting.
To roast the turkey:
Preheat the oven to 425 degrees and place a rack in the lower third of the oven. In a small bowl, stir together the melted butter and olive oil (for basting) and set aside.
Using paper towels, dry both the inside and outside of the turkey. Gently slide your fingers between the skin and the breast of the turkey to loosen the skin. Spread half of the softened butter between the breast and the skin.
Arrange twelve sage leaves evenly between the skin and the breast. Place the remaining sage in the cavity. Season with black pepper, including the cavity.
Truss the turkey, place the bird on it's back, and rub the remaining 2 tablespoons softened butter all over. Place in a roasting pan breast-side up. Pour 1 inch water into the bottom of the roasting pan. Lower the oven temperature to 325 degrees. Roast the turkey for 3 to 3 1/2 hours, basting every hour with the butter and oil mixture. Add additional water to the pan as needed.
Begin testing for doneness after 2 1/2 hours. A thermometer inserted into the thickest part of the thigh should reach 165 degrees, and the juices should run clear. Transfer the turkey to the carving board and tent with aluminum foil and allow to rest for 30 minutes.
To make the gravy:
Place the roasting pan with drippings over 2 burners and turn heat to medium-high. Add broth and bring to a simmer, scraping up the browned bits off the bottom of the pan.
Pour the contents through a fine-mesh strainer set over a large bowl. Using a large flat spoon, skim off and discard the layer of fat that floats to the surface, or pour the liquid into a fat separator and pour off the liquid, leaving the grease behind.
Transfer the liquid to a saucepan, place over medium-high heat, and simmer briskly. In a small bowl, add some of the liquid and the cornstarch and whisk together to make a slurry. Gradually whisk the slurry into the simmering liquid, then cook until the gravy thickens, about 5 minutes. Season to taste with salt and pepper.
On a large cutting board, place the turkey breast side up. Remove the truss. Begin carving one side of the turkey completely before moving on to the other side.
Removing the wing: Pull the wing away from the body and slice through the skin to locate the shoulder joint. Cut through the joint to remove the wing.
Removing the whole leg: Pull the leg away from the body and slice through the skin to locate the thigh joint. Cut through the joint to remove the entire leg.
Separating the thigh and leg: Cut through the joint that separates the drumstick from the thigh. Serve these pieces whole, or carve them by cutting off the meat in thin slices parallel to the bone.
Removing the breast: Cut along the breastbone while following the curvature of the bones. Using your hand or a carving fork, gently pull the breast meat away while using the knife to remove the meat from the ribs. Place turkey breast on the cutting board. For larger slices, slice the breast meat on an angle.
Repeat with the second side of the turkey. Arrange cut portions on a serving platter and pass the gravy separately.
Turkey: Look for a natural or heritage turkey with the words "no salt added" on the label. Stay away from "self-basting" or Kosher turkeys which are injected with a salt solution. Brining an already salted turkey will make the bird way too salty.
How much turkey: Plan on 1 1/4 pounds per person. If you can't find a turkey small enough for your group, consider a turkey breast instead. And if you're feeding a large group, consider a couple of medium or large turkeys rather than an enormous one (it is easier to thaw and cook a couple of average birds rather than the biggest one you can find).
Kosher salt: Used for dry-brining (aka pre-salting). The salt draws out the extra moisture in the turkey, forms a salt solution on the outer layer of the bird, and then is reabsorbed back into the meat to season it. For a wet-brine recipe, see my post on how to brine a turkey. Don't substitute standard table salt for the Kosher salt because it is much finer and much saltier.
Baking powder: Baking powder dries out the outer layer of the turkey resulting in deliciously crispy skin.
Chicken broth: Homemade chicken broth, or turkey broth, if you're one step ahead of things. If you like, you can simmer the neck and gizzards in water while the turkey roasts to make a quick version of turkey broth (discard the liver). Store-bought works, too.
Cornstarch: My trick for making an easy gravy that's also gluten-free.
Yield: Plan for 1 1/4 pounds turkey per person (some of the weight is from bones). This recipe assumes a 15-pound bird which will feed about 12 people (about 1 1/2 cups turkey per person or 18 cups total). The math is: 12 people x 1.25 pounds per person = 15-pound turkey.
Storage: Store leftovers covered in the refrigerator for up to 4 days.
Make ahead: Get a jump start on your Thanksgiving prep with my easy Make Ahead Turkey recipe. Roast, carve, and freeze the turkey in its juices. Then thaw, reheat, and make the gravy.
Thaw safely: The best (and safest) way to thaw a frozen turkey is slowly in the refrigerator over the course of several days. It takes longer, but it is infinitely safer. Never thaw a turkey using warm/hot water, in the microwave, or at room temperature, all of which let bacteria grow before the turkey is thawed.
Roasting times may vary: After all, you may be cooking a slightly smaller or larger turkey. An unstuffed turkey takes about 15 minutes per pound when roasted at 325 degrees. However, the best way to tell if a turkey is roasted through is with a good meat thermometer (165 degrees at the thickest part of the thigh).
Table-side carving: Follow this method if you prefer to carve the turkey at the table, rather than handle everything backstage. Just above the thigh and shoulder joints, carve a deep horizontal cut through the breast toward the bone to create a base cut. Starting near the breastbone, carve thin slices vertically, cutting downward to end each slice at the base cut.
Stuffing a turkey, chicken, or hen: For food safety reasons, and for a more evenly cooked bird, most modern recipes don’t encourage stuffing a turkey. If you decide to stuff your turkey, make sure the stuffing is warm when it goes in so it has a head start in cooking (either because you just finished making it, or because you made it in advance and reheated it). Use a large spoon or your hands to loosely stuff the body and neck cavities (do not pack it tightly because the stuffing expands while it cooks). Truss the main cavity with trussing pins to keep the stuffing inside. The stuffing must register 165 degrees on an internal thermometer to be safe to eat.