Pre-heat the oven to 400 degrees. Take the beef out and let it sit at room temperature for at least 30 minutes. Generously coat the beef with salt and pepper. Heat a metal sheet tray (or oven safe pan). When tray is hot add the butter. When the butter is almost melted, remove the tray and roll the beef in butter carefully and thoroughly, and put the tray back in the oven. Turn the beef over after 5-7 minutes.