You sauté something by cooking it in a frying pan with a small amount fat -- the smallest amount possible.
Sautéing is the most common use for frying pans and an important kitchen skill. If you know only one kitchen technique, it should be simmering; but if you know two, the second should be sautéing. Sautéing is the springboard for dishes without number and can be used (sometimes by making some adjustments) in every cuisine worldwide.
Most kitchen manuals tell you to heat the fat in the pan and then add whatever you're sautéing. Don't believe them.
(1) The only thing worse than hot fat splattering your shirtfront is hot fat splattering in your eye. There may be people who can drop material to be sautéed into the hot frying pan filmed with hot fat, but I am not among those people. Congratulations if you are, but are you?
(2) How much fat do you need? Successful sautéing requires using the least fat you can get away with. Start by filming the bottom of your frying pan, and I really mean filming. Put in a tablespoon of fat (two teaspoons for a small pan) and turn the pan every whichway, to anoint every square millimeter of the bottom surface. That's enough. Any more and you run the risk of making food so greasy you'll have to give it to the dog.
Please understand that when a sauté recipe tells you to use "1 Tablespoons of oil" or "2 teaspoons of bacon fat" you must note it but feel no obligation to follow it. The author is telling you the amount of fat she needed in her frying pan with her ingredients. The actual amount you need depends on many factors not calculated in her advice: the temperature in your kitchen; the worn or fresh surface of your frying pan; the age and provenance of your oil; your skill in filming the pan; the size and uniformity, or lack of uniformity, of your ingredients; and probably a thousand other things that I don't know to spell out.
If you are sautéing lots of small things, say chopped carrots, onions, and fennel, add them to the cold, filmed frying pan in a single layer and stir them thoroughly, till every chunk is coated very lightly with fat.
What if you have more than will fit in a single layer? If there's only a tiny bit too much, squeeze it in; ingredients shrink as they cook, so even if you don't have enough room at the beginning, you will soon. But if you have more than a tiny bit too much, sauté in two batches.
If you are sautéing one or more larger things, say fresh-caught trout, lay them on the cold, filmed frying pan in a single layer with plenty of space around each one.
What if you have more than will fit in a single layer? sauté them in two batches.
This cold-pan stuff is all well and good, you might say, but what about searing? Don't things need to be seared to keep the juices in?
Searing is an urban legend. It no more keeps the juices in food than getting a sunburn keeps your juices in. If you like the crusty brownness of seared food, sear at the end of the sauté rather than at the beginning; we'll get to that in good time.
Whether you're sautéing many small things or a few large things, you then put the pan on a brisk flame and heat it quickly, till you can hear the ingredients sizzling (wonderful sound). Once you hear the sizzling, stay with the pan. Sautéing is a high-heat kind of cooking. Don't try to sauté on a medium flame; grit your teeth, turn the flame up high, and don't get distracted.
Stay with the pan but don't stir. Don't stir! Somehow the enticing sound of the expression "to stir-fry" has seduced thousands of cookbook writers into telling you to "stir frequently" stuff that you're sautéing. No. Sautéing is a still technique; stir when you're stir-frying. Sautéing is not stir-frying.
If you're sautéing many small things, wait till the down-sides are cooked to your liking and then stir once to establish new down-sides. That's it. One stir, two at most.
If you're sautéing big things, use a pancake turner or a tongs to be check the down-sides and flip when the down-side is browned to your satisfaction. No stirring.
When everything is cooked through, if you'd like more brownness, turn the flame up even higher, or if it's already at its hottest point just stand there for a minute. Now's the time to sear, and the searing takes a minute at most.
Sautéing is fast but not easy -- not easy largely because it is so fast. But once you've mastered working that quickly, sautéing is one of the best friends you can have in your kitchen. Spread, heat, sizzle, stir or flip, done in a twinkling.
It seems to be impossible to write about sautéing without explaining that in French sautér means "to jump" or "to cause to jump." I have resisted this far, but now I must give in.
