Allow the eye of round beef fillet to sit out at room temperature for 1 to 2 hours.
Preheat the oven to 500 F. Place the eye of round beef in an foil-covered oven tray.
In a small bowl, mix together the garlic powder, dried rosemary, salt, black pepper, and olive oil. Then, massage this mixture into the beef.
Place the beef into the oven for 15 minutes, and then reduce the oven's temperature to 250 F, and allow the beef to slow roast for 1 hour, 40 minutes. Check the internal temperature with a meat thermometer until it reads at least 145 F, then remove it from the oven. Allow it to sit and rest for 15 minutes, before carving and serving.