Haven't tried this one myself yet, but found it in a book. Might give it a go sometime. Think it was you Franch who said you'd like the Fry's recipe - haven't done a search to check though! So for you and anyone else who's partial to Fry's peppermint cream, here it is....
Mint Biscuits
8ozs crushed arrowroot biscuits (think Rich Tea would be ok too)
1 bar Fry's peppermint cream
2 dessertspoons drinking chocolate
1 egg
4oz butter
4oz caster sugar
cooking chocolate
Melt the sugar, butter and Fry's bar in a saucepan and stir well. Add beaten egg, crushed biscuits and drinking chocolate.
Press into a tin and cover with melted chocolate. Place in fridge and when cold, cut into squares.