In a large pot, melt the butter over medium heat. Add the chopped onion, leek, carrots, and celery. Cook until the vegetables are softened, about 5 minutes.
Sprinkle the flour over the vegetables and stir well to coat. Cook for another 2 minutes to cook off the raw flour taste.
Slowly pour in the fish or vegetable stock while stirring constantly to avoid lumps. Add the bay leaves and dried dill. Bring the mixture to a simmer and cook for about 10 minutes, until the vegetables are tender.
Add the fish pieces to the pot and simmer gently for another 5-7 minutes, until the fish is cooked through and flakes easily with a fork.
Stir in the heavy cream and season with salt and pepper to taste. Simmer for an additional 2-3 minutes to heat through.
Remove the bay leaves from the soup. Taste and adjust the seasoning if needed.
Ladle the soup into bowls and garnish with freshly chopped parsley.
Serve the Norwegian Cream Soup hot with some crusty bread on the side. Enjoy!Note: Feel free to add other seafood such as shrimp or mussels to the soup if you like. Adjust the cooking time accordingly depending on the type of seafood you add.