Kosher salt is a coarse-grained salt that's great for cooking because it's easier to handle than ordinary table salt, and it adheres to food products better, too.
And since salt is by far the most important seasoning agent in the culinary arts, kosher salt is definitely a cook's best friend.
How Does Kosher Salt Taste?
Kosher salt has a cleaner, lighter taste than ordinary table salt. The iodine that's added to table salt imparts a slightly metallic flavor, but kosher salt is free of additives. (Also see: Iodized Salt)
What's the Equivalence Between Kosher Salt and Table Salt?
If you're substituting table salt in a recipe that calls for kosher salt, you should use half the amount of table salt as the recipe calls for.
For instance, if a recipe calls for 2 tablespoons of kosher salt, use 1 tablespoon of table salt instead. If you're converting the other way, use twice as much kosher salt as table salt.
How Coarse is Kosher Salt?
While Kosher salt is much more coarse than table salt overall, there is a bit of variation in crystal size among different brands of Kosher salts. If you use one particular brand for any length of time, you'll probably start to develop a feel for how much salt you're using.
If for some reason you have to switch to another brand, you may have to readjust to compensate for the different sized grains.
For instance, my preference is Morton, but sometimes all I can find at the store is Diamond Crystal, which has a little bit finer grains.
Can I Use Kosher Salt in Baking?
Because it doesn't dissolve as easily as table salt, kosher salt isn't the best choice for baking. Stick with table salt for breads, cakes, and other baked goods. (Although kosher salt is a great topping for homemade bagels, soft pretzels, and breadsticks.)
What Are Some Other Ways of Using Kosher Salt?
Kosher salt is also ideal for making spice rubs (because the salt crystals really grab onto the food), marinades, brines, and for canning and pickling. You can even use kosher salt for salt-rimming margarita glasses.
When boiling water for potatoes, vegetables or pasta, always salt the water generously. Not because it makes the water boil hotter, as some people claim, because it doesn't. But because it makes your food taste better! Water doesn't taste like anything, so food cooked in plain water will be bland and flavorless.
Some people say your water should be about as salty as seawater. This is a bit arbitrary, since not all seawater is equally salty. The point is, the water should taste salty. Add a little at a time and stir to dissolve. Then taste and add more if necessary. Remember, you can always add more. Of course if you oversalt, just toss out some of the salted water and add fresh water. Keep tasting until it's right.
Just be sure you salt the water before it comes to a boil, so you can taste it without burning your tongue.