1. Place the quartered potatoes in large saucepan filled with salted cold water. Bring to the boil and simmer for approximately 10-12 minutes or until tender.
2. While you are waiting for the potatoes to cook, place the haddock in a pan with the milk and some black pepper. Bring to the boil then put the lid on and simmer for 3 minutes. Remove the fish and keep the milk to one side for later.
3. Using a fork, separate the poached fillets into large flakes.
4. Fry the butter over a medium heat until bubbling then cook the leeks with a small amount of salt until tender.
5. In a large bowl, place the potatoes and roughly crush/mash with a fork. Add the haddock, leeks, 2 tablespoons of the leftover milk and some seasoning then gently combine. Shape into patties.
6. Set up a crumbing station by firstly putting the flour in a small bowl, then the eggs in another and lastly the breadcrumbs in a large bowl. Season all three.
7. Dust each patty with flour then dip in the egg and cover with the crumbs.
8. If you have a deep fat fryer then heat the oil to the required temperature and fry for 5-7 minutes. If not, heat a small amount of oil in a frying pan and cook the patties until golden brown on both sides.
9. Serve with your favourite condiments and some fresh crunchy salad leaves.