Wash basil, shake dry and finely chop the leaves of 6 stems. Cut butter into pieces. Knead flour, egg yolks, butter, 3 tablespoons cold water, chopped basil and 1 pinch of salt first with the dough hooks of the hand mixer, then with your hands to a smooth dough. Wrap the dough in foil and chill for about 30 minutes. Wash the tomatoes, dab dry and cut in half. Put mozzarella in a sieve, drain and dice. Mix eggs and cream and season with salt, pepper and nutmeg.
Roll out the dough 2-3 mm thin on a floured work surface and cut out 8 circles (approx. 12 cm Ø). Line 8 greased tartlet cups (each approx. 10 cm Ø) with the dough. Press the dough firmly at the edges, cut off any protruding edges and prick several times with a fork. Put tomato halves and mozzarella cubes into the tartlets. Pour egg cream over them and bake in the preheated oven (electric range: 200 °C/ convection oven: 175 °C/ gas: level 3) for 25-35 minutes. Cut the remaining basil leaves into thin strips and sprinkle on the tartlets before serving. Remove the tartelettes from the oven and remove from the tartlets
Waiting time approx. 1 hour