Basic Mashed Potatoes Recipe: 1) Put 2 pounds whole peeled russet or Yukon gold potatoes in a large saucepan and cover with water, add 2 tablespoons kosher salt. Bring to a simmer and cook until potatoes are tender about 45 minutes. 2) Drain potatoes, then peel and return to the pan, add 1 cup hot milk and ¼ to 1 stick room temperature unsalted butter. Mash with a potato masher or fork. Season with salt and pepper.