Method

Make your tart shells; sift cocoa powder and icing sugar. Transfer to bowl. Add in cold cubed butter and scrape down the sides and bottom of the bowl. Combine with egg yolk. Sift in the flour and combine well. Form into dough. Flatten the dough and shape it into tart shell moulds. Wrap and store in the refrigerator overnight.

Make your tart filling; In a large bowl, combine chocolate, butter, salt and 280 g of your total sugar. Warm over very low heat, stirring occasionally until all mixed. Allow to cool. Whisk all the eggs and remaining sugar to a fluffy, ribbon consistency. Fold the egg mixture into the cooled chocolate mixture in thirds, pausing to mix through properly. Transfer the mixture into piping bags. Pipe chocolate filling into tart shells. Bake for 9 minutes at 160°C preheated.

To serve
Serve hot (be warned, the centre of the tart will be very hot). Sprinkle with a pinch of sea salt to garnish and serve with your favourite choice of ice cream.