Preheat oven - 180C
In a large pan, cook the pieces of cod in water for 20 min.
Drain and flake it. Put it in a deep bowl, cover with very hot milk and allow to stand for about 1 hour.
Meanwhile, cut the onions and the garlic into slices. In a large pan, heat some olive oil and lightly brown the onions and garlic.
Cook the potatoes with the skin on. Let it cool, remove the skin and cut into slices.
Add the potatoes to the onions and garlic. Mix everything carefully.
Drain the cod from the milk and add to the potatoes.
Stir everything slightly and season with salt and pepper. Let it cook for another 2 mins.
Pour the mixture into a baking dish. Cut the eggs into slices and spread over the top. Drizzle with a little olive oil and bake for about 10-15 mins.
Remove from the oven, spread the olives on top and sprinkle with chopped parsley.