Bailey's Irish Cream Cheesecake

Crust
2 Mix the crumbs with the sugar and butter.
3 Press into the bottom and part way up the sides of a 9 inch springform pan.
4 Cover the pan bottom and sides on the outside with aluminum foil to keep any water out.
Cheesecake
7 Preheat the oven to 375F.
8 Melt the chocolate chips.
9 Set aside.
10 Beat the cream cheese with paddle attachment on lowest speed until smooth.
11 Add the sugar and continue to beat at low speed.
12 Add the eggs, one at a time, beating well after each.
13 Remove bowl from mixer and fold in the chocolate, the Irish Cream, vanilla, and sour cream.
26 Fold in until no streaks remain in the cream cheese mixture.
14 Pour filling into prepared springform pan and place it in another, larger pan.
15 Add boiling water slowly until it comes halfway up the sides of the springform pan. (this makes the bain marie)
16 Bake for [timer minutes=0]50 minutes[/timer].
17 Turn off the heat and leave the cake in the oven for [timer minutes=0]1 hour[/timer]. DO NOT open the oven door.
18 Remove from the bain marie, remove the aluminum foil, and let cool to room temperature.
19 Refrigerate for at least [timer minutes=0]4 hours[/timer] or overnight.
Ganache
22 Just before serving remove the cheesecake from the springform pan by carefully running a knife around the edge and gently opening up the hinge.
23 Heat the heavy cream until bubbles form around the edge.
24 Add the chocolate and stir gently until it melts and the whole mixture is blended.
25 Spoon over the chilled cheesecake and smooth the top.