Baked Decadent Cocoa Tart

For the pastry: sift the flour into a mixing bowl and rub in the butter until the mixture resembles breadcrumbs. Gradually add the water, until the mixture just comes together. Roll the dough into a ball, then wrap in cling film and chill for 30 minutes.

Heat the oven to 180°C (160° fan) 350°F gas 4. Grease a 23cm|9"pie dish or tin.

Roll out the dough on a lightly floured surface. Line the tin with the dough, pressing it into the base and sides, leaving 2cm|1" of dough hanging over the edge. Line the dough with baking paper and baking beans. Bake 'blind' for 10 minutes. Remove the beans and paper.

For the filling: mix together the sugar, flour and cocoa and set aside.

Whisk together the egg yolks and egg until well blended. Add the water and vinegar and whisk until frothy.

Pour in the butter and whisk until combined.

Gradually beat in the cocoa mixture until well mixed.