For the pastry:
80g dark chocolate, 75% cocoa
175g butter, cubed
230g caster sugar
4 egg yolks
50g cocoa powder
15ml lemon juice
250ml + 30ml coconut milk
160g dark chocolate, chopped
180ml coconut and cows milk
15ml coconut oil
a pinch of salt
Making the pastry:
Melt the chocolate and set it aside.
Add the butter, sugar, egg yolks, vanilla and milk to the bowl of a food processor and process to mix.
Add the chocolate in a thin stream while the engine is running.
Add the sifted cocoa and flour to the mixture and process until the mixture forms a smooth ball of pastry.
Wrap the pastry in plastic wrap and rest for 30 minutes in the refrigerator.
Roll out the pastry between two sheets of baking paper to a thickness of 3mm.
Line a loose bottom tart tin and then line the pastry case with tin foil. Freeze for one hour.
Preheat your oven to 180℃.
Bake the pastry case with the foil lining for 15 minutes. Remove the foil and bake for another 15 minutes.
Set aside to cool completely.
Making the blueberry custard:
Add the berries, lemon juice, 250ml coconut milk and honey to the bowl of a food processor and process until smooth.
Pour the 30ml coconut milk into a small bowl and add the cornstarch and agar-agar. Stir to dissolve.
Pour the blueberry mixture into a small saucepan over medium heat and bring to the boil.
Drizzle the cornstarch mixture into the blueberry mixture while whisking continuously until smooth and it starts to thicken.
Pour the blueberry custard into the cooled tart shell and allow to cool.
Refrigerate for 1 hour.
Making the ganache:
Add the chocolate, milk (pour whatever you have left of the coconut milk into a measuring jug and then fill up with dairy milk to 180ml), honey and coconut oil to a heatproof bowl set over a saucepan with simmering water. Stir until the chocolate has melted and you are left with a smooth mixture.
Pour over the blueberry custard.
Refrigerate the tart for 4 hours before serving.