put potatoes into cold water and bring to a boil. reduce the heat and simmer until tender, 15 to 20 minutes.

meanwhile, heat the butter and half and half in a small pot until the butter melts and the mixture is hot.

once thepotatoes are cooked, drain well in a colander and then return them to the pot. turn the heat back on to low and stir theotatoes to dry them. mash the potatoes until smooth and stir in the hot half and half and butter. add the shredded cheese by the handful, stirring to melt, and season generously with salt and pepper. stir in the chives. serve immediately.