Cover loosely with plastic wrap and refrigerate, 8 hours to overnight.
Remove roast from the refrigerator and allow to come to room temperature.
Preheat the oven to 200 degrees F (95 degrees C).
Mix butter, rosemary, thyme, and black pepper together in a small bowl.
Spread butter mixture over roast. Place roast in a large roasting pan.
Bake roast in the preheated oven until internal temperature reaches 115 degrees F (46 degrees C) for medium-rare, about 3 1/2 hours. Remove from the oven and tent with aluminum foil; allow to rest, about 20 minutes.
Meanwhile, increase the oven temperature to 500 degrees F (260 degrees C).
Once the oven has come up to temperature, uncover rested roast and return it to the oven. Bake until well-browned, 6 to 10 minutes. Slice and serve.