For the stracciatella tartlets, preheat the oven to 170 degrees convection. Separate the eggs. Beat egg whites with a pinch of salt until stiff.
Beat yolks with sugar and vanilla sugar until very foamy. Mix flour with cornstarch and baking powder and fold into yolk mixture with beaten egg whites.
Line a baking tray with baking paper and place dessert rings (8 cm) on it. Spoon or pipe just enough of the sponge mixture into dessert rings (18 rings) to cover the bottom.
If you don’t have that many dessert rings, you can also use a piping bag to pipe 18 circles (8 cm) on top. Bake for about 10 minutes.
Transfer the circles to a work surface sprinkled with sugar, immediately remove the baking paper and let cool.
Whip the cream with cream stiffener until stiff, fold in the grated chocolate. Use 3 circles for one tartlet.
Spread whipped cream on 1st circle, place 2nd circle on top, spread whipped cream, place 3rd circle on top and spread whipped cream again.
Decorate the stracciatella cupcakes with decorative chocolate leaves.