Preheat the oven to 350°F. Grease a 9-inch springform pan.
Prepare the shortbread base: In a large bowl, cream together the butter, sugar, and vanilla extract until light and fluffy. Add the flour and salt and mix until just combined. Press the mixture into the bottom of the prepared pan and bake for 15 minutes or until lightly golden in color. Remove from the oven and let cool completely.
In a large bowl, beat the cream cheese with an electric mixer until smooth. Add the sugar and beat until combined. Beat in the eggs, one at a time, and the vanilla extract until combined. Pour the mixture over the cooled shortbread base.
Bake for 45 minutes or until the edges are lightly golden and the center is set. Remove from the oven and let cool completely.
Prepare the cheesecake truffle topping: In a small saucepan, heat the heavy cream until steaming. Place the chocolate chips in a heatproof bowl and pour the hot cream over the chocolate. Let sit for 5 minutes, then whisk until smooth and shiny. Let cool to room temperature.
In a large bowl, beat the softened cream cheese until smooth. Add the cooled chocolate mixture and beat until combined. Pour the mixture over the cooled cheesecake filling and spread evenly. Chill in the fridge for at least 3 hours or until set.
Remove the cheesecake from the pan and cut into slices. Serve chilled.