Set cream cheese, eggs and sour cream on the counter for at least 4 hours for best results.
For the crust, mix chocolate cookie crumbs with melted butter and press into a greased 23cm/9” springform pan. Bake at 180°C/350°F for 10 minutes. Cool on wire rack.
For the filling, beat cream cheese until smooth. Add sugars and beat until fully combined and smooth. Add 2 eggs and beat until just combined. Scrape down sides of bowl and add remaining eggs. Add sour cream, bourbon and vanilla, beat until combined, stopping to scrape down bowl as needed. Do not overbeat.
Preheat oven to 180°C/350°F. Double wrap the outside of the springform pan with foil. Pour filling into the cooled crust. Jiggle the pan to smooth the top. Place the springform pan in a large roasting pan. Place in the oven and fill the roasting pan half full of water, being careful not to allow any water to get into the springform pan. Bake for an hour, or until cheesecake centre is slightly wobbly. Turn off the oven and prop the door open about 10cm/4”. Leave the cheesecake in the oven for 1 hour, then remove and cool completely on the counter. Cover and refrigerate until completely chilled, about 6 hours. It can be frozen, tightly wrapped, at this point.
For the sauce, melt the butter and brown sugar in a saucepan over medium heat. Stir and cook until beginning to bubble, 3-5 minutes. Reduce heat and whisk in milk and bourbon. Cook for another 3 minutes, stirring occasionally, until the sauce has reduced slightly. Stir in pecans and cool. Transfer to a serving bowl or jug and chill until ready to serve.
To serve, run a knife around the edge and remove the springform pan. Drizzle half the sauce around the edge. Cut into wedges, making sure to cut through the crust. Spoon more sauce over each piece if desired. Garnish with sweetened whipped cream and purchased chocolate sauce.
Room temperature ingredients will yield the smoothest cheesecake – do not skip this step!
Do not cover the cheesecake until completely cooled, as condensation inside the wrap may spoil the smooth surface.
For freezing, wrap cheesecake tightly and freeze for up to 1 month. Allow to thaw 2-3 hours and remove the springform pan. Refrigerate until ready to serve. Can be refrigerated for 2-3 days.
Freezing the sauce is not recommended, but it keeps in the fridge for 2 weeks.