Mix all dry ingredients for rub and coat both sides of steak. Cover and put the steaks into the fridge for at least 40 minutes. (Remove steaks and allow to sit on counter 30 minutes prior to grilling.).
While steaks sit, take out butter, garlic, and basil. Cut basil and use a garlic press to smash garlic, mixing both into the butter. Cover and place in the fridge. (Remove butter when taking the steaks out to come to room temperature).
Preheat grill. Place the steaks on the grill and cook until golden brown + slightly charred, about 4 to 5 minutes.
Flip steaks over and continue to grill (3 to 5 minutes for medium-rare, 5 to 7 minutes for medium, 8 to 10 minutes for medium-well.
Remove from grill and top with basil garlic butter. Tent loosely with foil and let rest 5 minutes on cutting board or plate before slicing.