On a large cutting board, lay the turkey out flat, skin down. If butchered correctly, it should resemble a mildly gruesome Rorschach test. Slice the two sides in half between the breasts. Set one half aside. Cover the half turkey with a piece of wax paper. Using the flat side of a kitchen mallet, or the underside of a frying pan, pound the bird to flatten it out. The thigh side will give more than the breast side, but in general, you want to flatten it to about half its given height. Gently separate the skin from three-quarters of the breast, enough to eventually allow the breast to roll onto the thigh portion without the skin attached. Salt the turkey with 1 ½ tablespoons of salt, reserving the remaining 1 ½ teaspoons for salting the skin once it's tied off. Set aside for 30-45 minutes while you prep. Preheat the oven to 450ºF. To a spice grinder or high-speed blender, add the porcini and grind to a fine powder. (It will go airborne, so unless you want to inhale porcini, let it settle for 20 seconds before removing the top.) In a food processor, combine the porcini powder and butter, and pulse until smooth and the mixture takes on the color of almond butter. (If you do not have a food processor, you can cube the room-temperature butter and integrate the porcini by hand or with a spatula.) Finely chop the parsley, rosemary, and thyme, combine with the lemon zest, and set aside. Use a spatula to spread half the porcini butter over the turkey. (If it seems like too much butter, you're doing it right.) Sprinkle the bird with half the freshly ground pepper (or enough to cover), granulated garlic, fennel pollen, and fennel seeds, reserving the rest for the other half. Finally, cover the bird with half the herb mixture. Fold the breast of the turkey, without skin, onto the thigh portion. Wrap the thigh portion, skin on, over the breast, and then pull the remaining skin over the rolled-up bird to close it. If you know how to tie a continuous knot, go forth, but I am not that fancy. Luckily, it works just as well to, using kitchen twine, tie off the bird from the ends, moving inward, about 1 inch apart. Just be careful not to tie it too tight. If these ends appear a bit messy, you can tuck them in and use a final piece of string to tie the whole thing off lengthwise. Use the remaining 1½ teaspoons of salt to season the exterior. Repeat the process with the second half of the turkey. Arrange both turkey halves on a half sheet pan (13x18 inches) along with the wings, if you so desire (just season with salt and pepper), and roast for 20 minutes at 450ºF. At this point, the bird should already be golden brown. Turn the temperature down to 350ºF, baste both turkey porchette and the wings, and roast for another 40 minutes, basting again at the 20-minute mark. Remove the bird, which should now have the appearance of well-oiled leather, from the oven, and let it rest for 30 minutes. Transfer to a cutting board and slice into quarter-inch rounds to serve. (If you want—and you probably want—reserve the juices, which will be infused with porcini butter, to make gravy. Or simply ladle the jus over the sliced porchetta rounds.) Don't forget that while this is great on its own the same day, it reaches its apex in a sandwich the next day.