To make the base, crush the biscuits in a food processor.
Melt the butter and then mix with the crushed biscuits.
Line a 20cm springform tin with baking paper and press the crumb mixture onto the base.
Spread the blueberries over the base and chill in the fridge until needed.
Beat the softened cream cheese with the sugar and vanilla until smooth.
Add the eggs and mix.
Pour the cheesecake mixture over the blueberries, tap the tin on the counter to release any air bubbles, and bake in a moderate oven, 170˚C for 45 minutes, or until until the cheeesecake is set. Let cool in the oven.
Add the blueberries, sugar and lemon zest to a meduim suacepan.
Cook on medium low heat until warm.
Mix the lemon juice with the cornflour. Slowly, while stirring, add to the saucepan.
Stir and cook for about 5 minutes.
Take off heat and store in an airtight container in the fridge until the cheesecake is cooled down.
When ready to decorate, remove the blueberry sauce from the fridge.
Whip the cream with the vanilla and icing mixture until it forms peaks.
Pipe the cream around the edge of the cheesecake.
Pour the blueberry sauce into the middle of the cheesecake.