Salt, it could be argued, is the most important ingredient in the global kitchen. As it performs the simple task of enhancing flavor, salt can also be used to leach out moisture in various preservation methods, tame the sweetness of baked goods and be manipulated into infusions of all sorts. Leslie Bilderback is a culinary instructor and the pastry chef at n/naka in Los Angeles. Her latest book, ”Salt: The Essential Guide to Cooking with the Most Important Ingredient in Your Kitchen,” has recipes for making white, pink and black salts from scratch.