If possible, brine the turkey for 24 hours before cooking. Remove the turkey from the brine and air dry for 1-2 hours. (Brining creates super moist flavorful turkey meat.)
Look at the turkey carefully to determine where you see the breast meat. Then flip the turkey over and find the backbone. Use strong kitchen shears to cut alongside the backbone, from one end of the bird to the other. Then cut along the other side of the backbone to remove it completely. Keep the shears very close to the backbone as to not cut off any meat.
Open the cavity of the turkey to find the breastbone. Now cut a shallow incision through the flexible bone, from one end to the other, yet not all the way through the breast meat and skin on the other side. This allows the turkey to be flattened. (See photos for reference.)
Place the turkey breast-side-up on a large rimmed baking sheet. Push the breasts down to flatten the turkey. Pull the drumsticks down and together to create the classic spatchcock shape. If there’s no room on the baking sheet, you can leave the legs folded in their natural position.
Fold the tips of the wings backward under the breast.
Pat the turkey dry with a paper towel. Then pour the melted butter over the top and rub (or brush) it over the entire surface of the turkey.
In a small bowl, mix all the herbs and spices for the turkey rub. Sprinkle the rub generously over the turkey.
Preheat a smoker to 350 degrees F. Once hot and ready, move the turkey off the baking sheet and onto the smoker rack. Close the smoker and cook the turkey for 1 ½ - 2 ½ hours until the temperature of the turkey breast reaches 165 degrees F. (Place the thermometer deep into the breast. The total smoking time is determined by the size/weight of the turkey.)
Preheat the oven to 350 degrees F. Move the racks, if needed, to allow for the height of the turkey. Once hot, place the turkey in the oven. Roast the turkey for 1 ½ - 2 ½ hours until the temperature of the turkey breast reaches 165 degrees F. (Place the thermometer deep into the breast. The total cooking time is determined by the size/weight of the turkey.)
Allow the turkey to rest for at least 15 minutes, before cutting and serving.