Preheat the oven at 175℃/350℉. Line the base of a 16cm radius springform pan with baking paper and cooking spray.
Blend the biscuits until you have a slightly course crumb, not too fine. Add melted butter and mix until well combined. Line the base and sides of the springform with the biscuit mix, about just under 1 cm thickness all around. Bake for 8-10 mins. Remove and allow to cool down.
In a large bowl, using a spatula, mix the cream cheese, sour cream, sugar and salt together. Mix until very smooth and slightly fluffy, about 5 minutes.
Add the eggs and mix thoroughly using a whisk, about 3 minutes. Add vanilla bean paste, fresh lemon juice and cornstarch and mix well, about 1 minute. Pour the batter into the biscuit base.
Pour boiling water into a separate baking tin and place it directly on the base of your oven and place the cheesecake above that, on the middle rack. Bake for 40 minutes at 175℃/350℉. Then turn the oven off, remove the water and leave the cheesecake in the cooling oven for another 30 minutes. Note: the water will ensure the cheesecake doesn't crack while baking.
Thereafter, remove from the oven and allow to reach room temperature. Then cover and place in the fridge for 4 hours or overnight.