Sweet Potato Gratin

Ingredients

• 6 oz gruyère cheese shredded divided
• 1.5 cups heavy cream divided
• 1.8 lb russet potatoes 
• 2 lb sweet potatoes 
• 1.5 teaspoons salt 

Equipment

• bowl
• oven
• knife
• wire rack
• aluminum foil
• mandoline

Directions

1. Preheat oven to 40
2. Cut sweet potatoes and russet potatoes into 1/8-inch-thick slices, using a mandoline or sharp knife. Toss together potatoes, 3/4 cup heavy cream, and salt in a large bowl.
3. Transfer to a lightly greased 2-qt. gratin dish, and spread potatoes into layers. Top with 1 cup Gruyre cheese.
4. Pour 3/4 cup more heavy cream over potatoes, and sprinkle with remaining 1/2 cup Gruyre. Cover loosely with aluminum foil.
5. Bake at 400 for 40 minutes. Uncover and bake 20 to 25 minutes or until potatoes are tender and cheese is golden brown.
6. Transfer to a wire rack; cool 5 minutes.