Cook 1 pound peeled and quartered russet potatoes in a pot of simmering water until tender, 30 minutes; drain. Heat 2/3 cup half-and-half and 2 tablespoons butter in the pot. Add the potatoes and mash. Stir in 1/2 cup grated truffled pecorino cheese, and salt and pepper. Cover and let stand 5 minutes.
Photographs by Con Poulos