Wash and peel the potatoes. Cut them into pieces and boil well. Strain and add the salt, milk and butter. The mixture needs to become like mashed potatoes. Separately, in a pan with a little broth and oil, break apart the mince until it stews and forms into small pieces.
Finally, sprinkle it with plenty of cheese and cover with foil. Stew over low heat for about 1 hour and 30 minutes.
Shortly before removing, take off the foil and let the cheese crisp.