1. Unlatch springform pan, flip the base over so the lip is on the underside, and cover the base with a sheet of non-stick baking paper, leaving a 4-cm (1½-inch) overhang.  Reassemble the pan and set-aside.
2. In bowl of food processor, pulse chocolates on high to a fine crumb.
3. Add cookie crumbs, sugar and salt and pulse to just combine.
4. With processor running, add melted butter through the feed tube and process, scraping down sides and bottom of bowl as needed, until crumbs are evenly moistened.
5. Transfer crumb mixture to the prepared springform pan.  Press the crumb mixture evenly and firmly on base and up the sides of the springform pan.
6. Transfer pan to a rimmed baking sheet and set-aside.

1. Place chocolate in a small, heatproof bowl.
2. In a small saucepan, bring cream to a simmer over medium heat.
3. Remove from heat and pour cream over chocolate.  Let sit for 2 minutes.
4. Using a flexible spatula, gently stir chocolate and cream until combined well; begin near the centre of the bowl and gradually work your way toward the edge, pulling in as much chocolate as possible, until the mixture is smooth and glossy.
5. Add Kahlúa and stir until combined well.
6. Remove crust from the refrigerator.  Pour half of the ganache over the base of the chilled crust.  Use an offset spatula to spread ganache evenly to sides of pan.  Reserve remainder of ganache; cover and let stand at room temperature to use later for decorating cheesecake.  (If chilling cheesecake overnight, store reserved ganache in the refrigerator; bring to room temperature and whip with a spatula prior to decorating cheesecake.)
7. Transfer pan to a rimmed baking sheet and cover lightly with a sheet of plastic wrap.  Chill in the freezer until ganache is firm, about 60 minutes.

1. Preheat oven to 180° C (350° F).
2. In a small bowl, stir together molasses, vanilla, espresso powder, brewed espresso and dark rum until combined well and espresso powder is completely dissolved, set-aside to cool.
3. In bowl of stand mixer fitted with paddle attachment, beat together cream cheese and mascarpone cheese at medium speed until smooth, about 2 minutes, scraping down sides, bottom of bowl and paddle attachment as needed.
4. Reduce mixer speed to low, gradually add the sugar and flour.  Beat until smooth, scraping down sides, bottom of bowl and paddle attachment as needed, about 2 minutes (do not over mix).
5. Add the cooled espresso mixture into the cream cheese mixture and beat to just combine at low speed.
6. Beat in the eggs, one at-a-time, at medium speed just to combine, scraping down sides, bottom of bowl and paddle attachment after each addition.
7. Remove crust from the freezer (keep on rimmed baking sheet); pour filling over firm ganache layer and using an offset spatula spread filling evenly to sides of pan.
8. Bake on baking sheet until top is brown, puffed and cracked at edges and centre 5-cms (2-inches) jiggles only slightly when pan is gently shaken, about 1 hour 5 minutes.
9. Remove cheesecake from oven and transfer to wire rack.  Cool 15 minutes while preparing topping.  (The surface of the cheesecake will cave slightly.)  Maintain oven temperature.

Sour Cream Topping {Copertura di Panna Acida}

• 355 ml (1½ cups) sour cream
• 75 g (1/3 cup) caster (superfine) sugar
• 2 teaspoons pure vanilla extract

1. In a small bowl, whisk together sour cream, sugar and vanilla until combined well.
2. Pour filling on top of hot cheesecake and using an offset spatula spread topping evenly to cover filling.
3. Return cheesecake to oven (keep on rimmed baking sheet) and bake until topping is set, about 10 minutes.
4. Remove cheesecake from oven; remove from baking sheet and transfer to wire rack allowing the cheesecake to cool completely away from drafts.
5. Cover loosely and chill in the refrigerator, at least 3 hours, preferably overnight.

To Decorate Cheesecake

1. Remove cheesecake from refrigerator.  To loosen cheesecake from springform pan, run a thin, sharp knife between crust and sides of pan; unlatch springform pan and carefully remove sides.
2. To remove cheesecake from base, grasp opposite sides of baking paper with your hands and carefully lift cheesecake (not too high) off the base of the springform pan and set down on kitchen countertop.  Pull cheesecake (grasping the baking paper) slightly off the edge of the countertop enough that you can position one hand safely on the underside and in the centre of the base of the cheesecake, and lift cheesecake up off the countertop.  With your free hand carefully roll down one side of the baking paper as you set down that side of the cheesecake onto cake plate or cake stand, then carefully remove the rest of the baking paper as you are setting the opposite side of the cake down.  (Whew!)
3. Transfer ganache to large pastry bag fitted with a small star tip.  (I used Wilton 21.)
4. To decorate cheesecake with a lattice top, pipe 6 or 7 diagonal lines on surface of cheesecake, spacing 2.5 cm (1-inch) apart.  Repeat piping in opposite direction.
5. Pipe rosettes of ganache around top edge of cake.  Decorate with chocolate covered espresso beans or chocolate whoppers.  Refrigerate until lattice is firm, about 4 hours.  To allow flavours to fully develop, make cheesecake a few days ahead, cover loosely with aluminum foil in a tenting fashion to prevent the foil from touching the lattice and chill in the refrigerator.
6. For best flavour, serve cheesecake at room temperature but cut slices when cheesecake is cold (much easier to slice when the cheesecake is chilled).  To cut slices, use a clean, thin knife dipped in very hot water and wiped dry with a kitchen towel (making sure to repeat this step with every cut).