Peel the potatoes and cut into uniform 1/2-inch pieces. Place into a 4-quart saucepan and cover with cold water by at least 1-inch. Cover, set over high heat and bring to a boil. Once boiling, remove the lid, decrease the heat to maintain a simmer and cook until the potatoes can easily be crushed with a pair of tongs, approximately 15 to 20 minutes. Drain in a colander.
Put the cream, butter, salt and pepper into the now empty 4-quart saucepan and place back over the heat until the butter has melted. Remove from the heat and set a food mill fitted with the smallest die, on top of the pot. Add 1 cup of potatoes at a time to the mill. Once all of the potatoes have passed through the mill, stir to combine. Taste and adjust the seasoning, if necessary. Serve immediately.