Boil potatoes with skin on. Peel potatoes. Mash potatoes preferably using a ricer. Add 2 egg yolks, flour, salt, and pepper. Mix dough until the consistency is such that it does not stick to your hands. Separate in small, manageable fists and roll out (over a dust of flour) into 1 in flutes. Cut into 1x1 in squares. Boil water. When water is boiling, add gnocci pieces and boil for about 2-3 mingnocci pieces will float when ready.