I realized my cooking had reached wackiness when I counted six kinds of salt in my cupboard. But I'm better now.
If you read the cooking magazines and watch the food shows, you may wonder about all the salty hoopla. After all, isn't it all just sodium chloride? How much is hype and how much is real? How many salts do I really need to stock?
My answer: One or two.
Kosher Salt vs. Table Salt
The salt I use 90% of the time is Diamond Crystal brand Kosher Salt.
How is Kosher salt different? Common table salt (the kind in the cylindrical carton) looks like little cubes:
Kosher salt is dried in a way that breaks up the structure and the grains are much less even. The grains don't pack together as tightly, so the product is "fluffier." A cup of Diamond Crystal Kosher salt weighs half as much as a cup of table salt. (Morton brand Kosher salt is in between -- fluffier than table salt but not as fluffy as Diamond Crystal).
Why is this good? The most important reason is that chefs don't use salt shakers! They like to sprinkle it by hand, so they can feel how much they are applying. The fluffy granules of Kosher salt are easier to control. Try it, you'll see.
The second reason is that Kosher granules are less likely to bounce, so they stay where they fall.
The last reason is that the granules don't fully dissolve when applied to dry or semi-dry surfaces such as freshly baked crusts or browned surfaces. The undissolved granules produce little sparks of saltiness which tickle the palate.
If the salt will be dissolved, it doesn't matter what you use, so you might as well use table salt, since it is so inexpensive. In low moisture baked goods, table salt is recommended, because its small crystals dissolve more easily, but the difference is slight and I don't usually bother.
I use so little salt that the cost is immaterial, so I use Kosher salt for everything, so that I don't need to stock two products.
A huge variety of sea salt products are available. Their colors and tastes vary, depending on where they are made. I tried several sea salts and found the differences subtle, at best. A taste test by one of the cooking mags and another test by Martha Stewart found the same thing. Use sea salt if you like it, but don't expect it to alter your results very much.
How much salt should you use?
Not so much.
The more I cooked, the more I noticed how horribly salty many prepared foods are. A well-prepared dish uses salt much more gently.
Salt accentuates other flavors by tickling the taste buds, turning them on so they are more sensitive. Try this: Make a bland dish such as pasta or broth, with no salt at all. Add salt, a little at a time and notice how the other flavors come alive. This happens even though you can barely taste the salt itself. Acidic ingredients like vinegar and lemon juice also do this. The Couscous Salad recipe illustrates this very clearly. The recipe includes both salt and vinegar and at the time they are added, you can very easily taste the effect.
Be aware of what kind of salt the recipe uses. A tablespoon of Diamond Crystal Kosher salt weighs half as much as a tablespoon of table salt, meaning it has less sodium chloride. Morton's Kosher is between the two.
One teaspoon of table salt = 1.5 teaspoons of Morton's = 2 teaspoons of Diamond Crystal.
You need to know what the recipe writer had in mind. In absence of any other clue, assume they mean table salt.
It's often a good idea to under-salt and add more to taste.
Note that in recipes that involve reduction -- boiling away some of the water -- salt (and other ingredients) will concentrate. A perfectly seasoned stew may be overly salty once the reduction is complete. This is especially likely with soups and sauces.
Salt as you go, adding a little salt at each recipe stage. Ingredients like beans and pasta absorb water. If you add the salt early, it will penetrate with the water, providing even seasoning and allowing you to use less salt in the rest of the dish.