– 1½ l water or good fish stock

Fish stock is a flavorful liquid produced by simmering fish bones, heads, and trimmings (along with aromatics such as onions, celery, and bay leaves) in water for 30-45 minutes. The resulting broth extracts gelatin, minerals, and subtle umami flavors from the fish skeletal structure, creating a delicate, seafood-forward base distinct from meat stocks due to its shorter cooking time and lighter body. Quality fish stock depends on using bones from white fish varieties (sole, halibut, cod) rather than oily fish, which can impart a rancid or overly assertive flavor.

Water, by contrast, is a neutral solvent that carries no inherent flavor; it is used in cooking to regulate consistency, dissolve ingredients, and conduct heat. In many recipes, the choice between water and stock represents a balance between ingredient cost, flavor intensity, and dish requirements.

Fish stock is essential in French cuisine (especially court-bouillon) and Scandinavian fish cookery, used as the foundation for sauces, braises, and soups where subtle seafood flavor is desired. It is commonly employed in risottos, bouillabaisse, chowders, and poached fish preparations. Water serves as a neutral alternative when stock is unavailable, though it yields less flavorful results; it is preferred in delicate preparations where the cook wishes to highlight the fish itself rather than add competing flavors. Both liquids are interchangeable by volume, though stock concentrations may be adjusted to match desired richness.