This is my favorite mashed potato recipe. These mashed potatoes taste as if they contain a great deal more fat than they do. I use buttermilk to mash the potatoes because it has a natural creaminess yet is far lower in fat than milk or cream, and I add a small amount of butter at the end, only after the potatoes have absorbed the liquid. The butter stays on the surface of the potatoes, its flavor readily discernible, imparting a truly rich finish. Be sure to use fine-textured, thin-skinned potatoes like Yellow Finns or Yukon Golds, which become extremely creamy when mashed. If made with baking potatoes, the result will be grainy and watery.
