Cook potatoes (with their skin on) in boiling water until tender. Allow the cooked potatoes to cool slightly, then carefully peel while holding potato with a kitchen mitt.
While still hot, puree potatoes through a ricer, food mill, or hand style cheese shredder and shred them into a large mixing bowl and allow to cool completely before proceeding. You can 'flip' the bowl to toss the potatoes to help them cool. Meanwhile, bring a large pot of salted water to a rolling boil.
Add the cheese, flour, salt, and pepper and toss again by 'flipping' the bowl (similar to sauteeing a pan over a flame).
Add in the egg and mix by hand to form a smooth, slightly sticky dough. Briefly knead the dough to incorporate the flour, being careful not to overwork. Cut the dough into 6 equal pieces and return them to the bowl.
Working in close proximity to the stove, lightly flour your hands, and have a fork ready. Roll each piece (one at a time) into a long rope, about 1/2-inch in diameter, flouring your hands lightly only if needed. Slice the ropes into pieces 1-inch pieces.
Holding one piece at a time, gently press and roll the balls of dough against the back tines of a fork so slight indentations are formed (dip the back of the fork tines in flour as needed). Repeat with each piece of dough either keeping the pieces on the counter (or you can drop them right off the fork into the boiling water as you make them).
Gently drop the gnocchi into boiling water and wait for them to rise to the top. Cook for 2 to 3 minutes more then remove the cooked gnocchi with a slotted spoon or skimmer. Pour sauce over top and serve.