Remove the beef tenderloin from the refrigerator and let it sit at room temperature for an hour.
This helps it cook evenly.
Preheat your oven to 500°F (260°C).
This high heat will give your tenderloin a beautiful crust.
Rub the beef with butter, then generously season with kosher salt and black pepper.
Be sure to cover all sides.
Place the beef in a roasting pan and enter it into the oven.
Roast for about 20-25 minutes for medium rare.
Use a meat thermometer to check the internal temperature.
When it reaches 125°F (52°C), remove from the oven.
Cover with foil and let it rest for 10-15 minutes.
This allows the juices to redistribute.