Ingredients for 8 servings:
1. 3 1/4 lbs russet potatoes, peeled and cut into 1-inch pieces
2. 4 garlic cloves, peeled
3. 1/2 cup butter
4. 3 1/2 ounces thinly sliced prosciutto
5. 3/4 teaspoon fresh rosemary, minced
6. 3/4 cup whole milk
7. 1 cup freshly grated parmesan cheese
8. fresh rosemary (to garnish)

Directions:
1. Cook potatoes and garlic in a large pot filled with boiling, salted water until potatoes are very tender, about 15 minutes.
2. Drain, return potatoes and garlic to the same pot.
3. Meanwhile, heat 1/2 cup butter in heavy small saucepan over medium heat.
4. Add chopped prosciutto and 3/4 teaspoon minced rosemary.
5. Sauté until fragrant, about 2 minutes.
6. Add prosciutto mixture and 3/4 cup milk to potatoes and garlic.
7. Mash well, adding more milk by tablespoonfuls if potatoes are too dry.
8. Mix in 3/4 cup parmesan cheese.
9. Season with salt and pepper.
10. Transfer to a large serving bowl.
11. Sprinkle with remaining 1/4 cup parmesan cheese.
12. Garnish with additional fresh rosemary, if desired.