Human: How do I cook the perfect roast beef? Assistant: 

1. Start by selecting a good quality cut of beef with enough marbling of fat to ensure it is tender and juicy.
2. Preheat the oven to 300°F (150°C).
3. Place the meat in a roasting pan with a little oil and spread it out evenly.
4. Add some vegetables to the roasting pan, like potatoes, carrots, celery, and onions.
5. Roast the beef in the preheated oven for about 20 to 25 minutes per pound of meat, or until a thermometer inserted into the thickest part of the beef reads 130°F (54°C) for medium rare.
6. Remove the beef from the oven and let it rest for 10 to 15 minutes before carving.