3 lbs. red potatoes, quartered
2/3 cup grated Parmigiano-Reggiano cheese
1/2 cup extra-virgin olive oil
salt and pepper to taste
Put potatoes in a large pot of salted water; cover and bring to a boil. Cook 15 minutes or until tender. Drain but save 3/4 cup of liquid.
Coarsely mash the potatoes, adding some of the reserved liquid for moisture. Use a large fork to stir in extra-virgin olive oil and Parmesan cheese. Salt and pepper to taste.