1. Wipe the meat with a damp cloth and season with freshly ground pepper.
2. Melt the butter in a heavy-based frying pan over high heat and brown the beef in it on all sides to seal in the juices.
3. Put the meat in an ovenproof casserole into which it will fit fairly closely. Shell the peas and put them round the sides of the beef, and pour the butter from the pan over the meat. Cover the casserole with a lid and cook in the centre of a pre-heated oven at 325°F (mark 3) for 2 hours. At this stage the meat will be rare, allow another 30 minutes for well-done meat.
4. Lift out the beef, carve into thin slices and arrange them on a warmed serving dish, surrounded by the peas.
5. Boiled new potatoes with a little chopped mint are ideal for this dish.