THESE WERE AWESOME! I have this book from Idaho that has about one hundred potato recipes, so my husband and I tried this recipe. It is a keeper!
Au Gratin Mashed Potatoes
4 pounds Yukon or Russet Potatoes
3 cups milk
1 ½ cups heavy cream or half and half
2 teaspoons salt
½ teaspoon white pepper
1 cup grated parmesan cheese
2 TB chopped fresh chives
Peel potatoes and slice thinly. Place in a large pot with milk, cream, and salt and pepper. Heat mixture over medium heat until it boils. Stirring frequently to prevent scorching heat until potatoes are tender and nearly all liquid evaporates, about 30 minutes. Crush potatoes with a masher to desired consistency. You may have to add more milk and check the seasonings.
Place the wire rack in the oven to about 6 inches from element. Preheat broiler to high. Transfer mashed potatoes to a 9×9 boiler-safe dish.
Sprinkle the Parmesan and chives over the top of the potatoes. Broil until Parmesan melts and browns, about 5 minutes.