Begin by peeling about 1.8 kg (4 lbs) of Russet or Yukon Gold potatoes, cut them into even chunks, and rinse under cold water.

Place the potato chunks in a large pot, cover with cold water, add salt, bring to a boil, and cook for 15-20 minutes until fork-tender.

Carefully drain the potatoes and return them to the pot, allowing them to sit on low heat for a minute to remove excess moisture.

Using a potato masher or ricer, mash the potatoes until smooth, avoiding overmixing to prevent gumminess.

Gradually pour in melted salted butter and hot milk or cream, mixing gently until fully incorporated, then season with salt and pepper to taste.