In a medium mixing bowl, mix the butter with garlic, rosemary, thyme, and Montreal steak spice. Use a fork to make sure everything is blended and evenly distributed.
Roast for 15 minutes on high heat and then reduce the heat to 325F and roast for another 45-50 minutes. See below for cook times depending on how you like your meat cooked.
Once roasted to your liking, transfer the meat to a cutting board. Tent it with foil, which means covering it loosely. Allow it to rest for 20-30 minutes. Slice it into as thin or as thick pieces as you’d like and enjoy!