This recipe is from my friend Karen.  It is one of my favorite cheesecakes, which is saying a lot.  I make the cheesecake the evening before I want to serve it.  Keep it in the fridge overnight.  Do the mousse topping in the morning and then let it stay in the refrigerator for a few hours.


Crust:
30 Vanilla Wafers
2 Tbl. Unsweetened Baking Cocoa
4 Tbl. Sugar
4 Tbl. Butter, softened

Filling:
6 oz. semisweet Chocolate, broken up
1/4 C. Butter
20 oz. Cream Cheese (room temp.)
2 Eggs
3 Egg Yolks
1 tsp. Vanilla Extract
1 C. Sugar

Chocolate Mousse Topping:
6 oz Semisweet Chocolate, broken up
1/2 C. Sugar
2 1/3 C. Heavy Whipping Cream

To make the crust:  Preheat oven to 350. Spray a 10-in spring-form cheesecake pan. Line the bottom with a circle of parchment paper.  Spray again.
In a food processor, combine vanilla wafers, sugar, cocoa and butter and grind until fine. Press the crust onto the bottom of the pan.

To make the filling:  In a bowl combine the chocolate and butter.  Microwave in 30 second intervals, (around 3 times) stirring after each until it is melted and smooth.  Don't over cook this.  Let cool slightly till just warm but still stirable.   In a food processor, combine the cream cheese, eggs, egg yolks, sugar and vanilla until well blended. Pulse in the chocolate mixture.  Pour over the crust. Bake 35 minutes or until set. Let cool completely, around 3 to 4 hours.

To make the topping:  In a bowl combine 1/2 c of the cream and the chocolate.  As before cook in 30 second intervals (around 3 times), stirring after each interval until mixture is melted and smooth.  Cool till barely warm.   In a deep, medium bowl, whip the remaining 2 Cups cream until stiff peaks form. Fold in the sugar and the chocolate mixture. Spoon onto the cheesecake and smooth top with a spatula.  Refrigerate till ready to serve, at least 2 hours.  Don't remove the sides of the pan until you are ready to serve it.