Place the fish, bay leaf and milk in a saucepan and simmer for around 5-10mins, turn the heat off and leave the fish in the pan until cooked through. Remove the fish from the pan and leave to dry on some kitchen roll.
In the meantime, boil the potatoes until they are soft, drain, then mash with some milk and butter, stir in the lemon zest, parsley and dill. Season with salt and pepper.
Break the fish into chunks and stir carefully into the potato mixture and leave to cool.
Pour the eggs into one bowl, the flour into another bowl and breadcrumbs in a third bowl.
Divide the mixture into 6 balls and then flatten to look like a fish cake. One by one, dip the fish cake into the flour, then into the egg and then cover in breadcrumbs and place on a plate, then repeat with the remaining fish cakes.
Place in the fridge for at least 1 hour.
Heat the oil in the frying pan and on a low heat, add the fishcakes and fry for around 5 - 10mins on each side until crispy on the outside and warmed on the inside.
Serve immediately with some salad and tartar sauce.