- 1,5 to 2 kg potatoes, scrubbed,
- 2 tablespoons plain bread crumbs,
- 1/4 cup (1/2 stick) unsalted butter softened,
- 2/3 cup warm milk,
- 1 cup plus 2 tablespoons freshly grated pecorino Romano or Parmigiano-Reggiano,
- 1 large egg beaten,
- 1/4 teaspoon grated nutmeg,
- Salt and pepper to taste,
- 200 gr fresh mozzarella, cut into 1/2-inch dice,
- 400 gr sliced Genoa or other Italian-style salami and/or prosciutto, chopped
- Place the potatoes in a large saucepan with cold water covering them completely.
Cover the pan and bring the water to a simmer over medium-high heat. Cook the potatoes until they are tender when pierced with a knife, about 20 to 30 minutes. Drain them and let them cool slightly.
- Generously butter a 2-quart baking dish.
Sprinkle the dish with the bread crumbs, turning it to spread the crumbs evenly.
- When the potatoes are cool enough to handle, remove the skins.
Place the potatoes in a bowl and mash them until smooth. Stir in 3 tablespoons of the butter, the milk, 1 cup of the grated cheese, the egg, the nutmeg, and salt and pepper to taste. Fold in the mozzarella and meat.
- Heat the oven to 400º.
Spread the mixture evenly in the dish, dot with the remaining 1 tablespoon of butter, and sprinkle with the remaining 2 tablespoons of grated cheese. (This dish can be prepared to this point and refrigerated for up to 24 hours.)
- Bake the dish until the top is browned and the center is hot, 40 to 45 minutes (50 minutes if it was refrigerated).
Let it cool for 10 minutes before serving.