Drain pears and apricots well on a sieve. Warm the milk slightly, crumble yeast into it and dissolve. Add soft fat. Put flour, sugar, 1 packet of vanilla sugar, salt and egg in a mixing bowl.
Pour yeast milk on top and knead everything with the dough hooks of the hand mixer to a smooth dough. Cover the dough and let it rise in a warm place for about 40 minutes. Put 3 apricot halves aside for decoration.
Roughly dice the remaining apricots and pears. Fold the fruit into the leavened dough. Grease the bottom of a springform pan (26 cm Ø). Fill in the dough and smooth it down. Cover and leave to rise in a warm place for about 20 minutes.
Bake in the preheated oven (electric oven: 200 °C/ gas: level 3) for 35-40 minutes. Remove the cake from the oven, remove from the springform pan rim with a knife and let it cool on a cake rack.
In the meantime, stir the mascarpone, remaining vanilla sugar, lemon juice and vanilla pulp with the whisk of the hand mixer until smooth. Cut the remaining apricots into slices. Remove the cooled cake from the tin and brush loosely with the mascarpone cream.
Decorate with the apricot slices and as desired with grated lemon and lemon balm.