Cut potatoes in chunks, place in saucepan with sufficient water, bring to the boil and simmer until soft.
Drain water and mash potatoes. If you prefer, the potatoes can be left in chunks and added to the soup.
Pour the milk into a saucepan, add the bay leaf, the parsley or coriander stalks and the haddock fillets.
Bring to the boil then turn down the heat and allow to simmer for around 3 minutes.
Turn off the heat and leave to let the haddock flavor infuse into the liquid for another 5 minutes or so.
Remove the fish and the bay leaf from the milk and set haddock aside to cool so you can later break the fish up into chunks. Discard the bay leaf.
Heat the butter in a separate saucepan and add the leeks that have been sliced into discs, stirring now and again to make sure they turn translucent and don't burn – this should take around 5 minutes.
Stir the mashed potato into the milk once you have removed the parsley/cilantro stalks, or you can combine potato and milk in a blender and instead of discarding the stalks they can be blended with the milk and mashed potato.
Add the leeks and stir the fish chunks into the soup carefully so the fish pieces remain larger to provide a texture contrast to the smoothness of the potato and milk mix and the leeks.
The fish is salty so you probably won’t need any extra salt – always taste before adding salt. It’s easier to add than to try and tone down an over salty dish.
Place the fish soup into bowls and garnish with a little chopped parsley or cilantro. If you want to add a little extra color to the bowl of soup add a fine sprinkle of dried paprika.
Serve with a slice of bread (link to Dutch oven articles)