Mix fish with egg, mashed potato if using or half the breadcrumbs, the herbs, lemon zest and seasoning.
Divide into six, form into cakes and set aside in the fridge to firm up.
When ready to cook roll the fish cakes in the remaining breadcrumbs and either bake in a hot oven (180°C) for 15-20 mins, or cook on a BBQ for 4-5 mins each side placing a square of tin foil under each one to prevent breaking up on the rack.
Shallow frying in sunflower oil for 3-4 minutes each side also suitable method.
Serve with a little salad and tartare sauce.
Chop 3-4 small gherkins or dill pickles finely and add to the natural yogurt with 1 tsp capers, a squeeze of lemon juice and salt and pepper