Mix 200 g flour, cocoa and baking powder in a bowl. Add sugar, vanilla sugar, 1 pinch of salt, egg and 125 g butter in pieces. Knead first with the dough hooks of the mixer and then briefly with your hands to a smooth dough.
Wrap in foil and chill for about 30 minutes.
Turn over a muffin tray (12 troughs), grease the outside of the tins well. Roll out the dough on the floured work surface in a thin layer of approx. 3 mm. Cut out 12 circles (each approx. 9 cm Ø) and place them on the greased muffin tins (see
Fig. below) and lightly press the edges all around. Bake in the preheated oven (electric oven: 200 °C/circulating air: 175 °C/gas: see manufacturer) for approx. 15 minutes. Let the tartelettes cool down for about 5 minutes, then carefully lift them off.
Let it cool down.
Cut the chocolate into pieces. Bring the cream to the boil, remove from the stove. Melt the chocolate in it. Let it cool down for about 30 minutes, stir in between. Pour the chocolate cream into the tartelets. Chill for about 1 hour.
Wash the strawberries, dab dry and clean. Place 12 whole strawberries in the middle of the tartelettes. Halve the remaining strawberries and spread around them. Heat the jam, stir until smooth and spread on the fruits.