Combine the beets and eggs in a tall cup and blend with an immersion blender until pureed, Set aside. Combine flour, salt, mashed potato and parmesan cheese in a large mixing bowl. Add in the egg and beat mixture and mix with a fork or spatula until the dough starts to come together. Using your hands, kneed the dough until the color of the dough is a dark purple-red and no white spots are visible. Let the dough rest for about 5 minutes, meanwhile get a pot of boiling water Started.