1. Wash and dry the meat and cut a lattice pattern into the fat. Stir together the pepper, Worcestershire sauce, 3 tablespoons of the oil, the cognac and the cayene, pour over the meat, cover and leave to marinate for 1 hour, turning the meat over from time to time.
2. Brush the roasting rack with the remaining oil and rinse the roasting tin in cold water. Lift the beef out of the marinade, pat dry and rub in a generous pinch of salt.
3. Place the meat on the roasting rack in the tin. Calculate the cooking time (see below) and roast on the second shelf from the bottom of a very hot oven (220°C, 425°F, gas 7) for the first 15 minutes; then reduce to moderate (180 c, 350f, gas 4) for the remaining time.
4. If the meat gives easily when pressed it is still bloody inside, if it only gives a little it is pink inside and ready for carving.
5. Carve into thin slices, pour the juices from the roasting tin over the meat and serve.
Rare - 15 minutes per 450 g (1 lb)
Medium - 20 minutes per 450 g (1 lb)
Well done - 25 minutes per 450 g (1 lb)