Whisk together egg yolk and cream in a bowl and set aside.

Add flour, sugar and salt to food processor and mix together on a slow speed until throughly combined.

Cut butter into 8 equal parts and scatter on top of flour mixture.

Pulse ingredients until they resemble granules.

Place food processor on low and while it's running slowly add egg mixture through feed tube.

Let processor run on low until ingredients convert into a dough.

Remove dough from processor and pat together and shape into a rectangular shape approx. 1 1/2 inches high.

Cut dough into 8 equal chunks them wrap them up separately and place them in the fridge or 1 hour.

Once dough has chilled grease each tart pan with some butter and set aside.

Sprinkle a little flour on your work surface and lightly coat your rolling pin.

Roll out each piece of dough to completely fill the tart pans, the dough should go beyond the edges of the pans.

Carefully place the dough in the pans, then with your rolling pin, roll over the top of each one to get rid of the excess dough.

Cut circles of parchment paper the size of the base of each tart pan and then place them on top of the dough, and place pie weights on top of the parchment paper.

Place in a preheated oven at 375 and cook for approx. 5-8 mins until golden.

Remove tart shells from oven and remove pie weights and parchment paper.

Place tart shells back into oven and cook for another 5-8 mins until base is golden too.

Remove from oven and allow to cool, then remove from tart pans.

Place mascarpone, sugar and 2 tsp of lemon zest in a bowl.

Split vanilla pod and scrap away seeds and add to bowl.

Whisk ingredients together with a hand mixer or whisk until thoroughly combined.

Place equal amounts of mascarpone mixture into the base of each tart shell.

Mix blueberries with 1 tsp of lemon zest then layer blueberries on top of mascarpone.

Place tarts in the fridge for one hour before serving.