For the fillet steaks with Madeira sauce, pat the steaks dry with kitchen paper. Press a little wide. Season on both sides with salt and pepper. Heat the oil in a frying pan.
Sear the steaks in it for 1/2 minute on both sides, then toast for another 3 minutes on each side so they are still pink inside. Arrange on a warmed platter and keep warm.
Loosen roast stock with beef broth. Thicken with cornstarch mixed in cold water. Add Madeira and season well. Arrange the fillet steaks with Madeira sauce separately and serve.