In a food processor fitted with a sharp blade, blitz the biscuits until finely crumbed and sandy in appearance. Pour in the melted butter and let the processor run on low speed until the mixture clumps together.
Tip into the base of a 9" springform pan and press down evenly and firmly, taking the mixture up to the sides of the pan as well. Place in the fridge for 30 minutes.
Preheat the oven to 160 C.
Make the filling about 10 minutes before the crust is done chilling. Wipe out the bowl of the food processor and add the cream cheese and yoghurt. Blitz till smooth, about 5 seconds.
Now add the sugar, lemon zest and vanilla and blitz to combine.
Add the eggs, one at a time, letting the processor run after each one for a few seconds. Once the third egg is added, let it run on low speed for another 5 to 10 seconds, until the eggs are completely incorporated. Remember not to over-beat the batter. Too much air in it will cause the cheesecake to crack. A hand mixer also works here and in fact, reduces the chance of over beating the filling.
Pour the filling over the chilled crust and tap the pan gently on the counter to remove any air bubbles.
Bake for 30 to 35 minutes, or until you see the edges are puffing up and lightly browned and the center is still wobbly. Let the cheesecake cool in the oven itself for 20 minutes, with the oven door slightly open.
Let the cheesecake cool to room temperature for another hour and you will see the center has firmed up. Place in the fridge for at least 6 hours, preferably overnight. Slice and serve!
Cheesecake must be stored in the fridge at all times in an airtight container. It can also be frozen for about a month. Happy baking!