How to make amazing mashed potatoes

Early in culinary school, I was having a serious conversation about mashed potatoes. "Well," someone said, recalling a line from his favorite cookbook, "No one ever dared to use as much butter as Joel Robuchon." The room went quiet, in awe of this legendary French chef who uses as much butter as potato in his version, mashed potatoes with a holy yellow halo. (Conversations like this were what made culinary school awesome.)

A year and a half later, just weeks from graduating, I found myself on the vegetable station of our school's classical French restaurant, making mashed potatoes, thinking about Robuchon. I peeled 20 pounds of potatoes every day, eyeing the butter in the cooler, counting out 20 blocks and imagining plowing them into my mashers. And you know what? I didn't dare.

It wasn't just that I was a wuss (I was), but because after making hundreds of pounds of mashed potatoes for weeks, I grew attached to them the way they were. I realized that they reach their highest form not through putting things into them (even a shit-ton of butter), but through technique, by knowing how to cook and dry the potatoes so they mash up fluffy, how to keep them hot so they stay smooth and velvety, how to add the milk and butter so that they're rich and round but still taste above all like potatoes.

These mashed potatoes have gravity. No matter what else is for dinner, your fork will just keep falling into them, over and over, until they're all gone and you start eyeing the bowl, imagining piling the rest of them on your plate.

Which potato to use?

The more starch a potato contains, the less inherent moisture, and this affects the texture dramatically. Low-starch and high-moisture, or "waxy," varieties, like red "new" potatoes, become very dense and thick when mashed — or pasty and gummy to their detractors. Moving up the scale, "all-purpose" and "chef's" potatoes like Yukon Golds have a moderate starch level and offer a nice, safe, wishy-washy, middle-of-the-road, convictionless compromiser's texture. And finally, high-starch varieties like russets or Idahos mash up light and fluffy — or dry and mealy if done badly.

My preference is for high-starch potatoes because of the wonderful play between the lightness of the potatoes and the grounding silkiness and richness of butter and milk, and the techniques I lay out below will solve any textural problems. But I'll be diplomatic about the other types, because having recently had a delicious French fry made from waxy potatoes — a mortal sin in the eyes of all French fry purists — I reserve the right to be an agnostic with preferences. (Is that like a friend with benefits?)

Amazing mashed potatoes

Serves 6

3 pounds russet or Idaho potatoes, peeled and quartered
6 ounces butter (equals 12 tablespoons), cut into chunks, at room temperature
12 ounces half-and-half
Salt and pepper (I prefer white pepper for this), to taste

Special equipment: Sorry, you're going to need a food mill or a potato ricer. Not that you can't make mashed potatoes with a tool that looks like a branding iron, but I'm talking about amazing mashed potatoes here, and only a food mill (you might know it as an "applesauce maker") or a potato ricer (which looks like an overgrown garlic press and usually costs only a few bucks) will thoroughly mash the potatoes, making them lump free, without shearing open the cells. A food processor or blender, on the other hand, will rip the cells apart, releasing all the starch inside them, and instantly turning your dinner into book paste. And didn't we get over eating glue in kindergarten?

1. Preheat your oven to 300 degrees (optional; see step 5 below).
2. Place potatoes in a heavy pot, cover them with cold water by an inch, and bring to a boil over high heat. When the water is boiling, add enough salt to make it taste nearly like seawater, and turn the heat down to a moderate simmer. (Starting them in cold water saves time and lets the heat penetrate the potato more evenly.) Cook the potatoes until a paring knife slips in and out of them easily; check them after 15 minutes, then every few minutes thereafter. Even though you're going to mash them to a pulp, it is possible to overcook them — the cells will burst, release starch, and absorb water. How gross does that sound? So be vigilant when they're nearly ready.
3. A few minutes before the potatoes are done, warm the half-and-half in a small pot. Try not to boil it, but you want it nice and steamy. What we're doing is making sure the potatoes stay hot at every step of the way, not just because hot food should be hot, but because this keeps them from turning stiff. When the half-and-half is warm, season it aggressively with salt and pepper — you want it tasting a little bit saltier than is pleasant, because this is going to season the potatoes later.
4. If you're using a food mill, set your colander in the bowl of the mill and drain your potatoes, letting the hot water warm up the mill. (If you're not afraid, you can heat up your potato ricer too, but don't burn yourself on the handle!)
5. Drain the potatoes thoroughly, spread them in one layer on a baking sheet, and put them in the oven to dry. While you're at it, get your mixing or serving bowl nice and hot in the oven, too. Check on the potatoes after 3 minutes or so, and give them a gentle turn. When all the steam has come off and the outsides of the potatoes look floury, they're ready. (Alternatively, you can dry them back in the pot over very low heat, stirring to release the steam, but I like the simplicity and consistency of the oven.) The idea here is to rid the potatoes of all the excess moisture, letting them be as fluffy and light as possible. Well, as fluffy and light as possible when you drench them in butter and cream, anyway.
6. Set the potatoes in the mill or ricer and purée into your hot bowl, alternating every few chunks of potato with some butter; this helps you mix them together evenly. Fold the whole mash a few times with a spatula or spoon, tasting in various spots of the bowl, to make sure the butter is evenly distributed. The butter, on top of being delicious, will coat the cells of the potato and keep the half-and-half from waterlogging them. Science is magic!
7. Pour in the hot half-and-half in a moderate stream, folding or whisking just until it's incorporated. The potatoes should be moist but still firm enough to hold their shape. If they're stiff, add a little more half-and-half. Taste, add salt or pepper if need be, and keep hot! (And try not to eat it all before dinner's ready.)