What are the key factors in making silky smooth (non gluey) mashed potatoes.
What technique has the best results?
Here is how we made pomme puree at the restaurant I used to work at, for a very well known (in Canada anyway) French chef:
Peel and boil as many potatoes as you need. Cook until slightly underdone.
Run the potatoes through a ricer/food mill. Then--this is key--scrape the result through a tami--a very fine mesh sieve. Most often used for sifting flour. Usually about 14-18" diameter, looks like a drum.
Return resulting potato to a pot, add melted butter, cream, salt, pepper, nutmeg to your desired consistency, stirring all the time.
If not serving immediately, chill as fast as possible, and reheat to order in a pan using a little more cream to loosen it up.
IMPORTANT: you must work as fast as possible; the potatoes need to stay hot the whole time or will become gluey.
Here's how I make mine, which I like and got my wife eating mashed potatoes for the first time since childhood.
I steam the potatoes rather than boil them, which results in something that tastes more like potatoes than the boiling version and avoids the waterlogged problem that mis-timing the boiling can bring.
Peeled and cut into chunks, I steam until tender.
I either just use a masher and enjoy the few leftover chunks or I use a ricer to mash them into the large bowl.
Then I add just a bit of butter, a few dollops of fat-free sour cream and then start adding milk. I keep adding milk and mixing by hand until they're creamy, which, based on what I've seen in other recipes, etc. is quite a bit more milk than is typical.
They even reheat fairly well.
Of course, I could just be deluding myself and mine are among the worst, most gluey around.
Many chefs swear by using a potato ricer instead of a mixer; it is said to be less likely to rupture the cell walls and produce glueyness. I just bought one, so I'll let you know how it works.
I find using Yukon gold potatoes work best, be sure to boil until tender all the way through. Don't over beat with a mixer, use medium speed, and add softened butter. Milk, cream, or sour cream will also increase the creaminess without making mashed potatoes sticky.
here's what I do, and I make mine different than most people here:
The kosher version: I slice the potatoes as thinly as possible then add them to a pot with boiling water and a little salt. When the water begins to boil, I cover the pot and lower the heat (to prevent the water from boiling over). Then I slice, dice and fry an onion. When the onion has reached a nice brown colour, I stop frying and put the onions (and any remaining oil) into a mixing dish. I then take the potatoes off the heat and strain them, washing them to remove excess starch. I add the potatoes to the mixing bowl, add two spoonfuls of mayonnaise (normally 5% fat) and about 1/4 cup olive oil. Then I mash and mix. On top of the potatoes I scatter paprika. If it were up to me, I would also add some sliced parsley, but the family doesn't like that.
I prefer to put the mashed potatoes (uncovered) into the oven for about half an hour at 75 centigrade, which dries them out and then use the oven's grill for a further ten minutes.
I can't say this is the best way, but it is different...
I use a slow cooker to make supper, anyway, so I wrap some potatoes in aluminum foil and stick them on top of the chicken (or whatever) that's in the stoneware. When it's time to eat, I take the potatoes out, peel them, and mash with a fork into a bowl. Then I stir in some hot water and a little salt, or some of the gravy from whatever was cooking in the crockpot. It comes out really good, and it's very simple :) I don't think it's gluey at all...