In a bowl, combine the mayonnaise, paprika, rosemary, thyme, sage, garlic powder, cayenne, salt, and black pepper. Mix well to create a flavorful herb-infused mayonnaise rub.
Remove any giblets from the turkey cavities. Pat the bird dry with paper towels, inside and out. This step is crucial for achieving crispy skin.
Generously coat the turkey with the mayonnaise mixture, both inside and out. Don't forget to carefully lift the skin and apply the rub directly to the meat (both breasts and thigh areas) for maximum flavor penetration. If desired and for more intense flavor and convenience, too you can do this step ahead of time (one day ahead). Make sure to bring the turkey to room temperature first before roasting if applying the rub ahead of time.
Place the halved garlic, lemon quarters, and extra herb sprigs inside the turkey cavity. This will infuse the meat with additional aromatics as it cooks.
Preheat your oven to 325°F (165°C). Place the turkey breast-side down on a rack in a roasting pan. Cooking the turkey this way helps keep the breast meat moist and juicy. Cover with foil and roast initially for 2 hours and 15 minutes (this estimate is based on my 12-pound turkey). Adjust the timing based on the size of your turkey. See turkey cooking time guide in the post above.
Flip a turkey that's been cooking breast-side down once the underside is nicely browned and the juices have begun to run clear. Adjust the time based on your bird's size. This usually happens after roasting at a lower temperature for the bulk of the total cook time. Flipping at this stage allows you to finish roasting the turkey breast-side up so the skin can brown and crisp during the final portion of cooking. Use protective mitts, flip the turkey carefully, then return it to the oven, breast side up, and cook until an instant-read thermometer registers 165°F (74°C) when inserted into the thickest part of the breast and the thigh. (Please read the note below if you don't fancy flipping the bird).
Once cooked, let the turkey rest for 30-40 minutes before carving. This allows the juices to redistribute, ensuring moist and flavorful meat.