2 1/2 pounds russet, or baking potatoes, cut into 1-inch chunks, about 7 to 8 cups of cut up potatoes
1/4 cup milk or half-and-half
1/4 cup butter
3/4 teaspoon salt
1/4 teaspoon freshly ground black pepper
Place potatoes in a 4-quart saucepan or Dutch oven; bring to a boil over medium heat. Reduce heat to low, cover, and simmer for 20 minutes, or until potatoes are tender.
Drain potatoes thoroughly; transfer to a large bowl. Add remaining ingredients to the bowl, and mash with a potato masher to desired consistency. For creamy potatoes, use an electric mixer.
Alternatives: mix in sour cream instead of butter for a different flavor. You can also add roasted garlic or Parmesan.