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 boil.
Once boiling, remove the lid and decrease the heat to maintain a simmer. Cook until the potatoes can be easily crushed with a pair of tons, approximately 15-20 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 butter has melted.
Remove from heat and rice into bowl. Add 1 cup of potatoes at a time to the ricer. Once all the potatoes have been riced, stir to combine. Drizzle in white truffle oil, taste, and adjust the seasoning if necessary.