- Cooking Time: 85 minutes
- Servings: 8
- Preparation Time: 30 minutes
- 1 (14.1-ounce) package refrigerated piecrusts
- 1 tablespoons chopped fresh rosemary
- 1/4 teaspoons freshly ground pepper
- 2 cups (8 ounces) shredded Gruyere cheese, divided
- 1-1/2 pounds Yukon gold potatoes
- 1-1/2 pounds sweet potatoes
- 1 teaspoon Kosher salt
- 2/3 cup heavy cream
- 1 garlic clove, minced
- Garnish: fresh rosemary springs
- 1. Preheat oven to 450 degrees. Unroll piecrusts on a lightly floured surface. Sprinkle rosemary, pepper, and 1/2 cup cheese over 1 pie crust; top with remaining piecrust. Roll into a 13-inch circle. Press on bottom and up sides of a 9-inch springform pan; fold edges under. Chill.
- 2. Meanwhile, peel and thinly slice Yukon gold and sweet potatoes.
- 3. Layer one-third each of Yukon gold, sweet potatoes, and salt in prepared crust. Sprinkle with 1/4 cup cheese. Repeat layers twice, pressing layers down slightly to fit.
- 4. Microwave cream and garlic in a 1-cup microwave-safe measuring cup at HIGH 45 seconds; pour over potato layers in pan. Sprinkle with remaining 3/4 cup cheese. Cover pan with heavy-duty aluminum foil. Place on a baking sheet.
- 5. Bake at 450 degrees for 1 hour. Uncover and bake 25 minutes or until potatoes are done and crust is richly browned. Let stand 10 to 15 minutes. Carefully transfer to a serving plate, and remove sides of pan. If desired, carefully slide gratin off bottom of pan, using a long knife or narrow spatula. Garnish, if desired