The Cooking Liquids Because fish don’t require prolonged cooking, there’s little time for fish and cooking liquid to exchange flavors and mellow together. Cooking liquids for fish are therefore either fairly neutral and discarded—salted water, or a mixture of water and milk—or are prepared ahead of time to develop their flavor. In the French tradition, there are two classic liquids for poaching fish: a tart, light infusion of vegetables and herbs, and a richer stock made from fish and vegetables.
Court bouillon, or “briefly boiled liquid,” is a mixture of water, salt, wine or vinegar, and vegetable aromatics, cooked together for 30–60 minutes into a medium