Sprinkle about ¼ to ½ cup KOSHER salt and a few tsps of black pepper, OR your favorite BBQ rub to both sides of the spatchcocked turkey.
Fill the hopper with pellets, start up the pellet grill, and preheat to 300-350°F. If your BBQ rub has a lot of sugar in it, choose 300°F. If you only used salt and pepper, go ahead and use 325-350°F.
Place the spatchcocked turkey on the pellet grill, directly on the grill grates with the breast side facing up and to the left.
Place an internal temperature probe if you have one into the center of one of the breasts, and another one, if you have one, into the middle of one of the thighs.
Close the lid, cook the spatchcocked turkey for about 2.5 to 3 hours, monitoring the temperature as it may cook faster or take longer.
When the internal temperature of the breast has reached 165°F, and the internal temperature of the thigh hits 175°F, remove the turkey from the pellet grill.