Set the oven at 180C/gas mark 4. Line the base of a 20cm springform cake tin with baking parchment. Place a pizza stone or baking sheet in the oven to heat up.
Put the cream cheese and caster sugar into the bowl of food mixer and beat for a few seconds until soft and creamy. Grate the lemon zest into the cheese, then add a drop or 2 of vanilla extract.
Break the eggs into a small bowl and beat lightly with a fork or small whisk to combine the yolks and whites. Introduce the eggs to the cream cheese beating at slow speed, then pour in the double cream. At this point the mixture may look too much like liquid but worry not.
Stir in the flour, making sure it is thoroughly combined then pour into the lined cake tin. Scatter in the blueberries, some of which will slide down into the depths, others will stay afloat.
Slide carefully into the oven, place on top of the hot stone or baking sheet and bake for 45 minutes, until the cake has risen a little, its surface soft yet lightly firm and patchily golden brown.
Remove the cheesecake from the oven and leave to cool before slicing.