Recipe by: The International Chocolate Cookbook
Serving Size: 12 slices
Preparation Time: 2 hours
4 ounces graham crackers (14 2.5 inch squares) -- coarsely chopped
2 1/2 tablespoons unsalted butter -- melted
1/8 teaspoon lemon zest -- finely grated
6 1/2 ounces top-quality white chocolate -- coarsely chopped
2/3 cup granulated sugar -- divided
1 1/2 pounds cream cheese -- at room temperature
2 large eggs
1/8 teaspoon lemon zest -- finely grated
1 1/2 tablespoons fresh lemon juice
2 teaspoons vanilla
2 1/2 tablespoons Grand Marnier
4 large egg whites -- free of yolk
1 cup sour cream
1 1/2 tablespoons granulated sugar
1 teaspoon vanilla
Position a rack in center of oven and preheat to 350. Very generously grease a 10-by-2.5 inch springform pan.
To prepare crust: Combine coarsely broken graham crackers, butter, and lemon zest in a food processor and process for about 1 minute, or until mixture begins to hold together. (Alternatively, combine graham cracker crumbs, butter, and lemon zest in a bowl and stir with a fork until mixture begins to hold together.) Pat crust evenly and firmly into bottom of springform pan; crust will be thin. Bake in preheated oven for 7 to 9 minutes, until lightly browned. Set aside on rack until cooled. Reset oven temperature to 400.
To prepare filling: In the top of a double boiler, over about 1 inch hot but not simmering water, slowly melt white chocolate, stirring occasionally, until chocolate in completely melted and smooth. Remove double boiler from heat and set aside with top still over bottom to keep chocolate warm. Combine 1/3 cup sugar, cream cheese, eggs, and lemon zest in a large mixer bowl. Beat on high speed for 5 to 6 minutes, or until very light and fluffy. (I've never gotten it fully to a state that I would call "light and fluffy, but that's what the recipe says). Add lemon juice, vanilla, and Grand Marnier and continue beating just until blended. Beat in white chocolate until very well blended and smooth. In a grease-free mixer bowl, beat egg whites on medium speed until frothy. Raise speed to high and beat just until soft peaks begin to form. Gradually add remaining 1/3 cup sugar and continue beating until firm but not dry peaks form. Fold egg whites into cream cheese mixture until evenly distributed throughout, but not overmixed.
Turn out mixture into crust, spreading evenly to edges. Shake pan to level the surface. Bake for 10 minutes. Reset oven temperature to 225 and continue baking for 50 to 55 minutes longer, or until mixture is barely set in the center when lightly tapped.
To prepare topping: (while cheesecake is baking) stir together sour cream, sugar, and vanilla, until well blended.
Remove cheesecake from oven and spread topping evenly over surface. Return to oven and bake 5 minutes longer or until topping is smooth and melted. Cool on a wire rack. Cover and refrigerate for at least 6 hours or until very cold. (cheesecake may also be frozen, removed from pan sides, wrapped, and then refrozen for up to 2 weeks.) Carefully run a thin-bladed knife around cheesecake to loosen it from pan sides. Gently remove sides. Serve cheesecake directly from the pan bottom. If desired, decorate with white chocolate curls, shavings, or fruit.
Serve with blueberry sauce.