Cook the potatoes in a pan of well-salted water (1 teaspoon of salt per 600ml) for 10–15 minutes. Once tender, drain the potatoes and leave them to dry in a colander for a few minutes, then mash well.

While the potatoes are cooking, put the haddock in a pan with about 500ml of water. Bring to the boil, then immediately turn off the heat, cover the pan with a lid and leave to stand for 8–10 minutes. Lift the fish out and when it’s cool enough to handle, flake the flesh and discard the skin and any bones.

In a separate pan, melt the butter and gently fry the leeks until soft, allowing any liquid to evaporate.

In a large bowl, mix the potatoes with the cooked leeks, grated cheese and parsley, then season generously with salt and black pepper. Gently mix in the fish, trying not to break the flakes up too much. Form into 6 patties.

Put the flour, beaten eggs and breadcrumbs in 3 separate bowls. Dip each patty into the flour, egg, then breadcrumbs. Heat the oil in a large frying pan and fry the fishcakes for 4–5 minutes on each side, until golden. Keep the fishcakes warm in a low oven if frying in a couple of batches.