Stir the Oreo crust ingredients together in a bowl with a fork. Pour into a 9-inch springform springform pan and pack in very tightly, going halfway up the sides. Freeze while you make the filling.
2 cups Oreo crumbs (about 24 Oreos), ¼ cup light or dark brown sugar, ½ cup unsalted butter, ¼ teaspoon kosher salt
Place the chocolate in a microwave safe bowl and microwave in :30 second increments, stirring in between each, until completely melted. Set aside to cool.
½ cup semi-sweet chocolate
Using a hand mixer or a stand mixer fitted with a whisk attachment, whip the heavy whipping cream on medium speed until soft peaks form, then increase the speed to high and whip until stiff peaks form. The whole process typically takes about 2-4 minutes. If using a stand mixer, transfer the whipped cream to another bowl.
1 ¼ cups heavy whipping cream
Using a hand mixer or a stand mixer fitted with a paddle attachment, beat the cream cheese and granulated sugar together on medium speed until smooth. Scrape down the sides. Add the sour cream, vanilla, and Baileys. Beat on medium speed until smooth and combined. Scrape down the sides again.
24 oz full-fat cream cheese, ½ cup granulated sugar, ¼ cup sour cream, 2 teaspoon vanilla paste or extract, ⅔ cup Baileys
Add the cooled, melted chocolate and mix on low to combine. Use a rubber spatula to get to the bottom and fold to combine any leftover streaks of chocolate.
Add half of the whipped cream to the cheesecake filling and use a rubber spatula to fold it together. Add the second half and finish folding it in carefully so you don’t deflate the air in the whipped cream.
Remove the crust from the freezer and spread the filling into the crust (an offset spatula is best for this job). Cover tightly with plastic wrap or aluminum foil and refrigerate for at least 6 hours, or up to two days. Overnight is best.
Use a knife or offset spatula to loosen the chilled cheesecake from the sides of the springform pan, then unclip and remove the rim.
To make the chocolate ganache, heat the heavy whipping cream and chocolate chips in the microwave in 30 second bursts, stirring in between each, until smooth. Stir in the Baileys until combined.
¾ cup chocolate chips, ¼ cup heavy whipping cream, 2 tablespoons Baileys
Allow the ganache to cool off so it doesn’t melt the top of the cheesecake, but still remains runny, and add to the top of the cheesecake. Use a spatula to smooth it out so it slightly falls over the sides and completely covers the top.
Add the heavy whipping cream, powdered sugar, and Baileys to the bowl of a stand mixer fitted with the whisk attachment (or to a bowl and use a hand mixer) and whip until stiff peaks form, about 1-2 minutes.
¾ cup heavy whipping cream, 2 tablespoons powdered sugar, 2 tablespoons Baileys
Spread on top of the chocolate ganache, leaving decorative swoops on the top. Add chocolate shavings or chopped chocolate covered espresso beans.
chocolate espresso beans or chocolate shavings
Using a clean sharp knife, cut into slices for serving. Clean the knife off completely in between each cut for cleanest slices.