Olive oil

I like cooking w/olive oil. It's expensive but thank god for the $6 liter bottle at Big Lots.

This is the most important item you can have for everyday cooking.  About 3 months ago I switched from the big Trader Joe's bottles to a premium olive oil from Napa.  It makes a huge, noticeable difference and I regret the years I could have been cooking with this elixir.

Salads, marinades, frying small things. . .I like it better than less-expensive oils. . .sort of a luxury item but I find it almost impossible to do without. . .

Right now, I've got olive oil, regular vegetable oil, peanut oil, and sesame oil, and yes, they're all used for different things.  Makes a world of difference to use the right oil for the right food (though olive oil and vegetable oil can generally be used for many of the same things, olive oil's got a better taste to it.  And you can't make decent fried chicken without peanut oil.  And sesame oil, though not something you "cook" with per se, just makes some stuff taste better when drizzled on).  The only thing I don't get is the difference in taste between regular olive oil, "virgin" olive oil and "extra virgin" olive oil.  Never had all three around at once to tell the difference.

Olive oil is a bit overrated as an essential. Sure you need it if you're going to make a gourmet meal, but for a lot of things plain old vegetable oil works almost as well for a lot less money.

I also use it almost every time I cook. I usually stick to the cheap stuff, though, especially those huge Trader Joe's bottles. I understand that some people treat olive oils like fine wines -- you can actually go into Grand Central market and find stores devoted exclusively to various grades of olive oil -- but I've never been able to justify to myself putting down $20 or even $10 for a bottle.

Nothing is more important.  I don't go a day without using olive oil.  Generally I actually will have two different bottles open at once, a higher quality for use as an ingrediant where the flavor is more important and a cheaper bottle for use in sauteing and other cooking applications.