1. Whip the cream. In a medium sized bowl, add the cold cream and using hand-held electric beaters fitted with the whisk attachment, whip on medium-high speed until stiff peaks form. Set aside.
2. Beat the cream cheese. (See note below on cream cheese) In a separate bowl, add the cream cheese and using hand-held electric beaters fitted with the paddle/beater attachment, beat on medium speed until smooth and creamy. Scrape down the base and sides of the bowl with a rubber spatula.
3. Add the remaining ingredients. (See note below on pumpkin puree) Into the cream cheese mixture add the pumpkin puree, powdered icing sugar, light brown sugar, Lyle’s Golden Syrup, spices and salt and beat on medium speed until smooth, creamy, and combined.
4. Fold in the whipped cream. Add the whipped cream to the pumpkin cream cheese mixture and fold through with a rubber spatula until fully combined. Take care not to deflate all the air in the whipped cream by over mixing.
5. Fill the biscuit base and refrigerate. Remove the biscuit crust from the refrigerator, or freezer, and pour the pumpkin cream cheese filling into it. Smooth the filling throughout the base and use an offset spatula to smooth off the top.
6. Cover tightly in plastic wrap and refrigerate the cheesecake for a minimum of 8 hours but I recommend leaving it overnight. This gives it the best chance to firm up.