Boil the potatoes in salted water until soft, drain well and mash. Leave to cool. Steam the smoked haddock for 8-10 minutes. Cool and flake, removing all the bones. Stir the smoked haddock flakes into the mashed potatoes. Add the melted butter and watercress and form into eight cakes on a well-floured board. Chill for 15 minutes.

Dip each cake into the beaten eggs, then the breadcrumbs and fry gently in hot oil for 3 minutes each side. Serve with a crisp mixed leaf and watercress salad.