Preheat oven to 350 degrees. Line the outside of a 9-inch springform pan with aluminum foil.

In a bowl, combine graham cracker crumbs and granulated sugar. Add melted butter and mix to moisten. Press into the bottom of the springform pan.

Bake crust for 10 minutes, then cool on a wire rack.

Reduce oven temperature to 325 degrees. Prepare a large roasting pan and boil about 4 quarts of water.

Blend cream cheese, sugar, and vanilla bean seeds until smooth. Add eggs one at a time. Mix in sour cream and heavy cream until combined.

Tap the bowl against the countertop 30 times to release air bubbles. Pour over the cooled crust and smooth the top.

Place the cheesecake in the roasting pan and pour boiling water halfway up the sides.

Bake until set but jiggly in the center, about 65 to 75 minutes. Turn off the oven and leave cheesecake in for 10 minutes.

Cool on a wire rack for 30 minutes, then chill in the refrigerator for at least 8 hours or overnight.

Melt white chocolate in a microwave-safe bowl until smooth. Let cool until lukewarm.

Whip heavy cream until soft peaks form, add sugar, and whip until stiff peaks form. Set aside.

Whip cream cheese with vanilla bean seeds until smooth. Mix in melted chocolate. Fold in whipped cream until combined.

Pour mousse over chilled cheesecake and spread evenly. Chill for 1 1/2 hours.

Whip heavy cream with optional vanilla bean seeds until soft peaks form. Add sugar and whip until stiff peaks form.

Spread whipped cream over mousse layer just before serving. Garnish as desired and cut into slices.