Separate the turkey into two halves by removing the backbone from the turkey with a sharp knife or kitchen shears. Removing the backbone is easy; click here for a video tutorial. Then, using the knife or shears, cut down the middle of the breastbone to create two halves of the turkey.
Light your grill and set up for two-zone cooking. Alternatively, you can use the oven for this. Set the temperature for either to 350° F.
While the grill or oven is preheating, melt one stick of butter over low heat, just till it melts. Then whisk in two teaspoons of Nashville Hot seasoning. Allow the butter to cool somewhat, but before it starts to become a solid again, inject it evenly into the breasts, legs and thighs. I use this meat injector but use what you have.
Coat the skin of the bird evenly with a light coat of a neutral oil. Avocado or grapeseed oil work well. Then, generously season the bird with Nashville Hot Seasoning.
Place the turkey on a raised-rim cooking sheet. Put it into the preheated grill over indirect heat or into the oven. Allow the turkey to roast until internal temperature reaches 150° F in the breast or 170° F in the thigh, as read with a dependable quick-read thermometer. Cooking time will depend on the size of the bird.
Remove the turkey from the grill or oven. Place it on another raised-rim sheet and tent with aluminum foil, allowing it to rest. While turkey is resting, strain the drippings into a small saucepan. Add an additional stick of butter and melt over low heat. Whisk in 2 teaspoons of Nashville Hot Seasoning and keep warm.
Carve turkey as stated in the notes below and drizzle with melted butter, drippings, and seasoning.