Knead the flour, almonds, butter, egg, sugar and vanilla sugar into a smooth short pastry. Cover and put in a cool place for about 30 minutes. Grease the moulds (10-11 cm Ø / 150-175 ml content).
Roll out the short pastry on a floured work surface and cut out 9 circles (each approx. 13 cm Ø). Line the moulds with them. Press on the dough and cut off any excess dough. Place a round piece of parchment paper on the dough and add peas.
Bake in the preheated oven (electric cooker: 200°C/ gas: level 3) for approx. 20 minutes. Remove parchment paper and peas and bake the tartlets for 5-10 minutes. Remove from the tartlets immediately and let them cool down.
Soak gelatine in cold water. Sort the blueberries, wash and drain. Puree 2-3 tablespoons blueberries and cassis. Mix with yoghurt, sugar and lemon peel. Squeeze out the gelatine, dissolve, stir into the yoghurt and refrigerate.
Whip the cream until stiff and stir in as soon as the yoghurt cream begins to set. Spread into the tartlets and chill until the cream is firm. Spread the rest of the blueberries on top and sprinkle with lemon julienne and blueberry leaves and decorate as desired.
Makes nine cupcakes.