Preheat the oven to 160°C fan/ 180°C.
Place the Custard Cream's in a blender and blitz until they form a breadcrumb texture
Melt the butter and add the biscuit crumbs, stir to combine. Place in the base of the 7" inch loose bottom tin. Spread in an even layer, then flatten.
Place in the oven for 8 minutes, before leaving on the side to cool.
Meanwhile, to make the filling combine the cream cheese and caster sugar together.
Add in the soured cream and whisk until a loose mixture is formed
Add in the plain flour and custard powder beating until the mixture is smooth.
Gradually beat in the eggs and egg yolk one at a time.
Pour the cheesecake mixture on top of the base, pour in dots of raspberry coulis and stir around with a cocktail stick gently. Place the remaining custard creams on top and bake in the oven for 40 minutes.
After 40 minutes turn the oven off and allow to cool in the oven with the door ajar.
Once the oven is cool you can remove the cheesecake to cool completely before removing from the tin.