Wash the samphire thoroughly under cold water. Steam over a pan of boiling water for 5 minutes, so that the samphire has softened just slightly but maintains a great crunch.
Meanwhile, melt the butter in a frying pan over a medium heat and add the scallops. Cook for 1 minute and then turn and cook for a further 2 minutes. Add the samphire and toss with the scallops. Season well then transfer to a serving dish and add the Old Winchester cheese. Divide between four starter serving plates and serve with lemon wedges.