Clean fish remove fins, tail and bone leaving head on. This takes ages and I recommend using tweezers to get out the tricky bones once spine has been removed.
Place breadcrumbs in a bowl, adding chopped parsley, chives, lemon juice and rind, half the onion, dash of cider to moisten, season well and let breadcrumbs swell.
Stuff fish with mixture.
Butter pie dish and place a layer of sliced potatoes on bottom.
Place stuffed fish in sideways so filling doesn’t fall out.
Mix together chopped hardboiled eggs, remaining onion, potatoes and rest of mixture and some more chives then fill gaps around fish. Season well and add the rest of the cider.
Roll out pastry and cut slit at the edge to let the fish head poke through.
Glaze pastry with beaten egg.
Preheat oven to gasmark 7 and bake for 10 minutes.
Reduce heat to gasmark 4 and continue cooking for 20 minutes until golden brown.