Starry Night Tarts

To make the pastry, sift the cocoa, flour, icing sugar and 1/2 teaspoon salt together, place in a food processor with the butter and process until fine crumbs form. Add the egg yolk and pulse just until the mixture comes together. Wrap in plastic wrap and refrigerate for 30 minutes. Roll out on a lightly floured work surface and line 4 individual, 3cm deep, loose-bottomed tart pans. Prick the bases with a fork and freeze for 30 minutes.

Preheat the oven to 180°C.

Line the tart shells with baking paper and fill with pastry weights or baking beans, bake for 10 minutes then remove paper and weights or beans and return to the oven for a further 5 minutes. Remove and cool.

Increase oven temperature to 190°C.

To make the filling, place butter and chocolate in a heatproof bowl over simmering water, making sure bowl does not touch the water, and stir until smooth. Set aside to cool slightly. Beat eggs, yolks and sugar together until thick and creamy. Add chocolate and stir well, then pour into the cases. Bake for 8 minutes, remove and cool. While the tarts are cooling, make the chocolate stars.

Place the white chocolate in a pan over simmering water. When melted, spread out onto a tray lined with baking paper to a thickness of about 5mm. Refrigerate for 10 minutes. Press a small star-shaped cutter into the chocolate to make several indentations, then return the chocolate to the fridge for 45 minutes to harden.

Use the cutter again to press into the star shapes and cut through completely, remove stars to a separate tray and keep refrigerated until serving time. To serve, pile raspberries onto the tarts, place white chocolate stars on top of raspberries and dust with icing sugar.