Bring a medium pot of water to a boil and generously salt. Carefully lower the potatoes into the water. Boil until they are fully cooked through and tender. Drain the potatoes.
Place a food mill over a large bowl and run the cooked potatoes through the food mill (A food mill will give you that silky smooth, creamy mashed potato. If you don’t have a mill, you can mash the potatoes with a potato masher or wooden spoon for a chunkier version).
Meanwhile, in the hot empty pot that the potatoes were boiled in, heat the milk, butter, a pinch of white pepper, and a pinch of sea salt on low. Add the potatoes to the pot and start to slowly combine the ingredients. Add the cream and continue stirring. Taste. Season with more sea salt if necessary.