Preheat the oven to 200℃ (180℃ fan)/400°F/gas mark 6. Cut the potatoes into small even-sized chunks and place in a saucepan with enough water to just cover. Bring to the boil, add a pinch of salt then reduce the heat and simmer for 10–15 minutes until just tender.
Meanwhile, cut the fish into bite-size pieces and divide between 2 individual pie dishes or one larger dish.
Beat the cream cheese, crème fraîche and milk together. Finely slice the spring onions and add to the cheese mixture along with the dill. Season and stir to combine. Pour over the fish.
Once the potatoes are cooked, drain well and return to the pan. Add the butter and mash. Pile on top of the fish then bake the fish pies in the oven for 20 –25 minutes until the top is crisp and golden and the fish is cooked.
You can add a few cooked prawns to the fish if you desire. Nutrition information is calculated using an online nutrition database - is approximate and is meant as a guideline only. (It does not include seasoning with salt and pepper.)