Mascarpone and Raspberry,White Chocolate Cheesecake

Preheat oven to 300F.
For the crust:
Place the biscotti and nuts in the bowl of a food processor fitted with a steel blade.Process in several short bursts.The crumbs should be like graham cracker crumbs. Melt the buttr in a saucepan, then stir in the biscotti/nut crumbs.
Press the crust mixture into the bottom of a 9-inch springform pan. bake at 350 for 10 minutes to set the crust.

For the filling:
With a mixer on medium speed (high speed will beat air into the filling and the baked cake will not be creamy)beat the mascarpone and ricotta in a large mixing bowl until smooth. Beat in the egg, a little at a time.
Add the sugar and beat until the sugar has dissolved, and the mixture is smooth and creamy. Melt the white chocolate in a heat proof bowl over a saucepan of simmering water (double boiler). Stir the melted chocolate into the cheese mixture. 
Scatter the raspberries over the crust, pour the cheesecake filling over the berries. Bake for 1 hour or until just set.
Turn off the oven and let the cake sit there until completely set and cooled.
Remove the cheesecake from the oven when cool and gently remove the sides of the pan and place the cheesecake onto a servng plate.
Make the topping by mixing together the marscarpone and ricotta cheese in a bowl and spreading it over the top of the cheesecake.
Decorate with the white chocolate curls and the fresh raspberries.