Pre-heat the oven to 570 Fahrenheit (300 Celsius).
Place the meat in the oven until it becomes nice and brown all over, approx. 20-23 minutes. Lower the temperature to 390 Fahrenheit (200 Celsius). Insert a thermometer into the meat at its thickest point. Allow the meat to continue roasting for 1.5-2 hrs, until the core temperature is somewhere between 136-140 Fahrenheit (58 and 60 Celsius) for medium. Remove the meat from the oven and allow it to stand for 20 minutes before cutting it.
Serve with oxtail sauce (see related recipe) and boiled vegetables.