A potato ricer, which has a perforated bowl for holding the boiled potatoes and two long handles that, when squeezed together, force the potatoes through holes in the bottom of the cup, is the best tool for preparing light, even-textured mashed potatoes. Look for a sturdy metal ricer with at least a 2-cup bowl; a good ricer should come with two disks with different-size perforations that can be inserted into the cup.