Rinse and quarter the potatoes. In a large pot, bring salted water to a boil. Add the potatoes and cook for about 15 minutes over medium- high heat, or until thoroughly cooked and soft. Drain.

In a large, heavy skillet set over medium heat, add the chunks of butter. Once it melts and begins to bubble, stir in the scallions and cook for a couple of minutes until they soften. Add the chopped chipotle chile and combine well. Add the cooked potatoes along with the milk.

Using a potato masher or a wooden spoon, mash the potatoes roughly as you mix them with the chipotle and scallion mixture. Sprinkle with salt and freshly ground pepper to taste. Serve hot.