Guiness Chocolate Cheesecake

Guinness Chocolate Cheesecake from LJWorld.com.

Crust
1 1/4 cups crushed graham crackers
2 tablespoons unsweetened cocoa powder
1/4 cup butter, melted
1 teaspoon instant coffee (optional)
In a bowl, stir together graham cracker crumbs, cocoa and coffee (if you are using it). Add melted butter. Stir together until well-combined. Press mixture evenly on the bottom of a 9-inch springform pan.
Filling
24 ounces cream cheese
1/3 sugar
5 teaspoons cornstarch
3 eggs
1 egg yolk
1/2 cup Guinness
2 teaspoons vanilla extract
1 cup semisweet chocolate chips
Combine cream cheese, sugar and cornstarch. Beat until smooth. Add eggs and egg yolk, one at a time, beating well after each addition. Add Guinness and vanilla. Stir until well-combined. Stir in melted chocolate. Pour mixture over crust. Bake at 350 degrees for 15 minutes. Lower the temperature to 200 degrees and bake for 1 hour and 10 minutes or until the center no longer looks wet or shiny. Remove the cake from the oven and run a knife around the inside edge of the pan. Turn the oven off. Return the cake to the oven for an additional hour. Chill, uncovered, overnight.
Glaze
1/2 cup semisweet chocolate chips
4 tablespoons of heavy whipping cream
1 teaspoon instant coffee
In a small saucepan, melt chocolate chips in cream over low heat, stirring constantly. Stir in coffee until dissolved. Spread the warm mixture over the cheesecake. Chill until serving time.