Step 1: Prepare the Crust

1. Preheat the oven to 325°F (163°C).
2. In a medium bowl, combine the chocolate cookie crumbs, sugar, melted butter, and salt. Stir until the mixture resembles wet sand.
3. Press the mixture evenly into the bottom of a 9-inch springform pan.
4. Bake the crust for 10 minutes, then remove from the oven and let it cool while you prepare the cheesecake filling.

Step 2: Make the Cheesecake Filling

1. In a large bowl, beat the softened cream cheese with an electric mixer until smooth and creamy. Scrape down the sides of the bowl.
2. Add the sugar and espresso powder, mixing until fully combined.
3. Add the eggs one at a time, beating well after each addition. Mix in the sour cream, heavy cream, and flour until smooth.
4. Pour the filling into the cooled crust, smoothing the top with a spatula.
5. Bake the cheesecake at 325°F (163°C) for 55-65 minutes or until the edges are set but the center still has a slight jiggle. Let the cheesecake cool on a wire rack for 1 hour, then transfer it to the fridge to chill for at least 4 hours (overnight is best).

Step 3: Make the Fudge Topping

1. In a small saucepan, melt the chocolate chips, heavy cream, butter, and espresso powder over medium-low heat, stirring constantly until smooth and glossy.
2. Remove from heat and stir in corn syrup for extra shine (optional).
3. Let the fudge topping cool for 5-10 minutes, then pour it over the chilled cheesecake, spreading it evenly with a spatula.
4. Return the cheesecake to the fridge for at least 30 minutes to allow the fudge topping to set.