3-pounds Yukon gold potatoes
3 tablespoons butter
3 tablespoons flour
3 cups heavy cream
⅔ cups grated parmesan cheese
2 ½ teaspoons salt, divided
1 ½ teaspoons black pepper, divided
1 cup Jarlsberg cheese, shredded
Preheat oven to 325 degrees.
Peel the potatoes and very thinly slice them on a mandoline or by hand.
Melt the butter in a large saucepan and add flour. Whisk for 1 minute until bubbly. Add the heavy cream and whisk frequently until a thick sauce forms. Add 1 ½ teaspoons of the salt, ½ teaspoon of the black pepper, and ⅓ cup of the parmesan cheese. Continue whisking until well-blended and very thick, about 1-2 minutes.
Coat a 9” x 13” baking dish with non-stick cooking spray. Spread ¼ of the potatoes in an even layer in the bottom of the pan. Season with ½ teaspoon each of the salt and black pepper. Top with another ¼ of the potatoes.
Pour half of the cream sauce over the potatoes and spread evenly. Top the sauce with another ¼ of the potatoes, season with remaining ½ teaspoon each of the salt and pepper. Top with the remaining sauce.
Sprinkle the Jarlsberg over the top of the sauce and then the remaining ⅓ cup of the parmesan cheese.
Cover tightly with foil and bake for 40 minutes. Remove the foil and bake for an additional 20-30 minutes until lightly browned and the potatoes are very tender.
Remove from the oven and let rest for 20-25 minutes before cutting.