Pumpkin Cheesecake

This is the dessert I'll be making for our family this Thanksgiving.

Crust:
1 1/2 cups graham cracker crumbs
3 tablespoons sugar
3 tablespoons melted butter
1/2 teaspoon cinnamon

Filling:
2 (8 ounces each) packages cream cheese, softened
1 cup half-and-half or whipping cream
1 cup canned pumpkin
3/4 cup granulated sugar
4 eggs, separated
3 tablespoons all-purpose flour
1 teaspoon vanilla extract
1 teaspoon ground cinnamon
1/2 teaspoon ground ginger
1/4 teaspoon ground nutmeg
1/4 teaspoon salt

Topping:
1 cup sour cream
2 tablespoons sugar
1/2 teaspoon vanilla extract

Combine crust ingredients; press into bottom and about 2 inches up the sides of a 9-inch springform pan. Bake at 325° for 5 minutes. In a large mixing bowl, combine cream cheese with cream, pumpkin, sugar, egg yolks, flour, 1 teaspoon vanilla, spices, and salt. Beat until smooth. Beat egg whites until stiff; fold into the pumpkin mixture. Spoon batter into crust. Bake at 325° for 1 hour.
Combine topping ingredients; spread over cheesecake and bake 5 minutes longer. Chill thoroughly before serving, and store leftovers in the refrigerator.