is there any benefits to season all salt? in cooking?

If you would like to experiment with spices, first you should buy a bottle of minced garlic and put it in a lot of your dishes, from a teaspoon to a tablespoon. Another spice that really kicks up a lot of dishes is Italian seasoning. Cooks should also have some Wondra Flour for thickening, and some Gravy Master for browning stews.

You've asked a number of different questions.

So first, "expert" cooks seldom use Season All Salt or most of the other "complete" spice mixes that have been premixed then bottled. (That doesn't mean YOU shouldn't use them, of course, and especially when learning more about cooking, which flavors and combinations you like, and just trying to make food taste less bland.)

Those "expert" cooks will, however, buy and use at least some of the pre-made mixes but usually ones without salt added (e.g., lemon-pepper, Old Bay, cajun mixes, chile powder, curry powder, etc). Most of the time though they'll tend to make up their own mixes of spices and herbs for using (sometimes including salt, or they'll add the salt at another stage during prep or cooking time).

The salt-based *jarred* spice/herb mixes have ingredients that are decided on and mixed up by a company like McCormick, Morton, etc (or by prominent chefs like Emeril, e.g.), and then sold as "general mixes," sometimes especially "for chicken" or fish, etc. Those mixes often have a load of salt in them though, which also makes them cheap to manufacture.

1. Morton's Season All Salt mixture contains the following ingredients (also in order of largest ingredient proportion to smallest):

...salt

...chili pepper, black pepper, celery seed, red pepper, garlic, onion, paprika

...cornstarch, silicon dioxide (to keep ingredients from clumping)

...annatto (for color)

2. McCormick's Season All Salt mixture has almost the same ingredients:

...salt

...chili peppers, black pepper, celery seed, nutmeg, coriander, onions, paprika, garlic

...maltodextrin (a sugar)

...silicon dioxide (clumping)

...annatto (for color)

(I tend to like the all-purpose mix called "Nature's Seasoning" made by Morton myself, but generally use it only as a shortcut for sprinkling on oven-baked chicken while hot.)

Here are some of the ways that all kinds of cooks use Season All and some of the other general seasoning mixes:

https://www.google.com/search?q=recipes+for+using+...

Once you get a little more used to cooking with seasonings, you'll be amazed at all the ways they can make foods taste(!), and that's a really fun part of experimenting with cooking. There's more info about using herbs and spices in cooking, as well as on some of the herb/spice combinations that various cultures/cuisines tend to like when put together (also called "flavor profiles") in these links:

http://answers.yahoo.com/question/index?qid=201111... (see my answer here)

http://www.tablefare.com/loveyourspices/collection... (indiv. spices are discussed on same site)

As for other "benefits," both herbs and spices are highly nutritional (partly because they've been concentrated by drying), and more of their health benefits are still being discovered every day.

Salt/sodium (which is a mineral, not a spice or herb) however, is essential for life but too much of it isn't healthy for most people. It's hard to avoid in pre-packaged and restaurant food though because sodium does all kinds of things for shelf life, and more.

As for tomato paste, that isn't an herb or spice but it is a kind of seasoning especially when it's concentrated in paste form. (I like to buy a small can, then freeze it in a ziptop bag pretty flat so I can just break off as much as I need for a particular dish and not waste.)