Season both sides of steak with salt, pepper, garlic and red pepper flakes. Rest steak at room temperature for 2 hours.
While steak rests, mix Cowboy Butter ingredients into medium-size bowl.
Once mixed, place butter on parchment paper and form into a horizontal cylinder. Roll parchment paper around it, twist each end and refrigerate for at least 15 minutes.
Create 2 cooking zones and reverse-sear your steak.
Once prepped, grill steak on indirect heat. Close lid and grill at 250°F for 25 minutes. Once internal temperature reaches 105°F, move steak over to direct heat. Grill each side for 2 minutes.
Take steak off grill, let rest for 10 minutes and top with slice of Cowboy Butter.