Add the potatoes and garlic to a large saucepan
, cover with cold water and add 2 large pinches of salt. Bring to a boil, reduce to a simmer
and cook until a fork can easily pierce the flesh, 20 to 25 minutes.
Meanwhile, heat the cream and milk in a small saucepan until just simmering. Cut the heat, stir in the butter to melt
and season with a big pinch of salt and pepper.
the potatoes in a colander
. Add them back to the pot they were cooked in and place over low heat to get rid of excess water. Once dry, turn off the heat and mash
the potatoes with a wooden spoon. Stir in the warm cream mixture and the truffle
cheese and Parmesan
. Season with salt and pepper.