Soak fish in water at room temperature for 24 hours, changing water periodically.
Make breadcrumbs from day-old bread. Combine with fresh chopped garlic, fresh minced parsley, and salt and pepper (all to taste).
Thinly slice enough potatoes to cover the bottom of the pan. Sprinkle with olive oil. Cut up fish and lay on top of potatoes.
Cover fish with breadcrumb mixture. Sprinkle with additional olive oil and a little bit of water. Cover with foil and bake at 350F for 35-40 minutes, or until potatoes are tender