Countries like Norway have always had ready access to both saltwater and freshwater fish. So it's no secret that fish is a key part of the traditional Norwegian diet, and it's prepared in a wide variety of tasty waysusually with very few ingredients. This soup is no exception. It's simple to prepare and adaptable to what's on hand. Like all soups, you can 'stretch' it by adding more of everything in the same pot. (For another version of Norwegian fish soup, see Grandpa Solberg's soup recipe).
Potatoes. Use all-purpose white potatoes (they have the ideal mixture of tenderness and firmness) or, lacking those, select Yukon Gold or russets. If your spuds are really fresh, scrub rather than removing the peels.
Stock/water. You'll get more flavor and nutrition by using chicken, vegetable or fish stock for at least part of the liquid. Use low-sodium, MSG-free stocks.
Fish. I prefer salmon fillets, but firm white fish such as cod, haddock, hake, or pollack are also fine choices. So are scallops. If frozen, remove the fish from the package and thaw in a bowl of cold water. Remove any bones and skin. Lay uncut fillets in soup; they flake apart when cooked.