This easy, reliable Thanksgiving turkey recipe uses a quick marinade in the food processor, and it always turns out awesome. The main flavor agents are garlic and salt, but you really don't get a strong garlicky flavor after it's cooking. It's super mellow, and really juicy.
4-5 days before roasting (depending on the size of your turkey), start thawing your turkey in the refrigerator. Budget about 1 day of thawing time for every 5 pounds. On the day before you plan to roast it, make the marinade by combining the garlic, salt, black pepper, olive oil, and butter in the food processor. Pulse until you have a very fine paste.
Put your carrots, celery, and onions on the bottom of your roasting pan. This will be the roasting "rack" that your turkey will sit on.
Remove the turkey from the package. Remove the neck and the giblets from the turkey cavity and give the bird a good rinse with cold water. Pat it thoroughly dry with paper towels, and lay it breast side up in the pan.
Spread half of your marinade all over the top side of the turkey, making sure you cover every surface and crevice, including the cavity. Flip the bird over so it's laying breast side down, and spread the other half of the marinade over this side of the turkey. Cover the roasting pan tightly with plastic and allow to marinate overnight. You can also spread some marinade over the neck and the giblets and add them to the roasting pan as well.
On the morning of the big day, take the turkey out of the fridge and let it sit on the counter (so you're not putting a cold turkey directly into the oven, which can prevent it from cooking evenly). About 3 hours before you're ready to eat, preheat the oven to 425 degrees F and arrange the oven rack so it's in the lower third of the oven. Take the plastic off your roasting pan and lift up the turkey to empty any liquid that might have accumulated in the cavity as it sat out on the counter. Make sure the wings are tucked in, and roast at 425 degrees for 1 hour, rotating the pan halfway through.
Remove the turkey from the oven and lower the temperature to 325 degrees. Using clean kitchen towels or a sturdy wooden spoon, flip the turkey breast-side up. Roast the turkey at the lower temperature for another hour (for a 12 pound turkey) to an hour and a half (for a 14 pound turkey), until the thigh registers 165 degrees and the juices run clear (i.e. not pink). Rotate the pan halfway through the second roasting process as well.
Remove the turkey from the oven, transfer to a carving board or serving plate, cover loosely with foil, and allow to rest for 20-30 minutes before carving.
Now, we know everyone has their own method for gravy, but here's ours: tip all the drippings from the roasting pan into a gravy separator. You want about 10 tablespoons of fat and 6 cups of the juices. If you don't have enough of either, you can add butter (if you need more fat) and chicken stock (if you don't have enough juice). In a large saucepan over medium heat, add the turkey fat and/or butter. Gradually stir in enough flour to make a roux, whisking constantly. Continue whisking until the roux turns a dark brown color, about 10 minutes. Slowly whisk in the turkey juices and/or broth. Season with salt and black pepper to taste. Simmer until thickened (when it coats the back of a spoon, it's perfect). If it's too thick, add more broth or water. That's it!