Prepare the Crust

Preheat Oven: Preheat your oven to 325°F (165°C). Grease a 9-inch springform pan and line the bottom with parchment paper.

Make the Crust: In a medium bowl, combine the graham cracker crumbs, sugar, and melted butter. Press the mixture evenly into the bottom of the prepared pan.

Bake: Bake the crust for 8-10 minutes, until lightly golden. Remove from the oven and let it cool completely.

Make the Cranberry Sauce

Cook the Cranberries: In a medium saucepan, combine the cranberries, sugar, water, and orange zest (if using). Bring the mixture to a simmer over medium heat and cook for about 8-10 minutes, or until the cranberries have burst and the sauce has thickened.

Cool: Remove the sauce from heat and let it cool completely. You can strain the sauce if you prefer a smoother texture, but leaving the cranberries whole adds a nice texture.

Prepare the Cheesecake Filling

Beat the Cream Cheese: In a large mixing bowl, beat the softened cream cheese and sugar until smooth and creamy. Add the sour cream and vanilla extract, and mix until combined.

Add Eggs: Add the eggs one at a time, mixing on low speed after each addition until just combined. Be careful not to overmix.

Pour into Crust: Pour the cheesecake filling over the cooled crust and smooth the top with a spatula.

Bake the Cheesecake

Bake: Bake the cheesecake in the preheated oven for 50-60 minutes, or until the center is just set and slightly jiggles. Turn off the oven, crack the door, and let the cheesecake cool in the oven for 1 hour.

Cool Completely: Remove the cheesecake from the oven and let it cool to room temperature, then refrigerate for at least 4 hours or overnight.

Prepare the White Chocolate Mousse

Melt the White Chocolate: In a small saucepan, heat 1/2 cup of the heavy cream until it begins to simmer. Remove from heat and stir in the chopped white chocolate until melted and smooth. Let the mixture cool to room temperature.

Whip the Cream: In a separate bowl, beat the remaining 1 cup of heavy cream until soft peaks form. Set aside.

Mix the Mousse: In another large bowl, beat the softened cream cheese, powdered sugar, and vanilla extract until smooth. Gradually fold in the melted white chocolate, then gently fold in the whipped cream until the mousse is smooth and fluffy.

Assemble the Cheesecake

Add the Mousse Layer: Spread the white chocolate mousse evenly over the chilled cheesecake layer.

Top with Cranberry Sauce: Spoon the cooled cranberry sauce over the top of the white chocolate mousse, spreading it out evenly.

Chill: Refrigerate the assembled cheesecake for at least 2 hours to allow the layers to set.

Serve

Garnish and Slice: Garnish the cheesecake with white chocolate shavings or fresh cranberries if desired. Slice and serve chilled.