Equipment
Ricer, food mill or masher for mashed potatoes?
The short answer. A ricer or food mill gives the smoothest, lightest mash because it breaks the potato without overworking the starch.
A masher leaves some lumps and is fine for rustic potatoes. A blender or mixer ruptures the starch and turns the mash gluey.
Restaurant-style purée uses a ricer or food mill, then beats in butter and warm milk.
Question
Which potatoes are best?
Yukon Gold are a reliable choice. Waxy potatoes also work well. Russets give a fluffier, drier result.