This method is from America's Test Kitchen program on PBS. There are scientific reasons for using this method with the mid-cooking cool down, but I won't bore you with them.

Mashed Potatoes

Peel your potatoes, either russet or Yukon gold, and cut into pieces, not too large, not too small. Rinse them off. Steam them over hot water in a vegetable steamer or colander, covered, for about 10 minutes. They won't be done. Pull the colander out of there and cool the potatoes down in cold water at the tap. Return them to the pot over the hot water and continue steaming until done.

Drain them, rinse in hot water, and set aside. In the cooking pot melt butter, about 2 tablespoons and add 1/2 cup milk and 1/2 teaspoon salt. Use a potato ricer to mash the potatoes into that hot mixture. Stir to combine and taste to see if it needs more salt.

The best way to serve is to shape the potatoes into a mound like a volcano. Make a dip in the top and put a pat of butter there to melt. Yum!

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These came out very nice and fluffy, but it was a lot of work using the potato ricer. For one thing it didn't hold very much so I had to run several batches of potatoes through it. This would be stressful to do with a house full of people waiting to eat. I prefer by Foley food mill, which the potato scientists would frown on because they would think that was too much working of the potatoes, or I would use an old-fashioned potato masher.