Salt and pepper
Cook or steam the potatoes. Take the fish filets and put them into a wide pot with 0.5 cm of water. Lowsteam the fish covered for as long as it takes to cook it properly. But not too hot! also boil the eggs. When the eggs are finished cut them in medium sized pieces. Warm up 250 (or how much you want) butter and put in the egg pieces and the cut parsley.
When all is finished serve the fish with the butter sauce on top and the potatoes aside.