Directions

1. Preheat oven to 350 degrees F (175 degrees C ). Mix together graham cracker crumbs, 1/4 cup sugar, and 1/4 cup melted butter or margarine. Press mixture into the bottom of a 9 1/2 inch springform pan. Bake 10 minutes. Cool. Don't turn the oven off.
2. Place potatoes in a baking dish. Bake until a knife inserted in center goes through easily, about 1 hour. Don't turn oven off. Cool sweet potatoes enough to handle, peel, and puree.
3. Transfer 1 1/2 cups of sweet potato puree to a large bowl. Add cream cheese, 3/4 cup + 2 tablespoons white sugar, sour cream and 1/4 cup cream; beat until smooth. Beat in eggs one at a time, blending well after each. Pour filling into crust.
4. Bake until tester inserted in center comes out clean, 1 hour. Turn off the oven. Let cake stand 1 hour in oven with door ajar.
5. Combine brown sugar and 1/4 cup butter or margarine in a heavy small saucepan. Stir over low heat until sugar dissolves. Increase heat, and bring to a boil. Mix in 1/4 cup cream, then nuts. Pour hot topping over cheesecake. Refrigerate.