Cream butter and icing sugar. Add 1 pinch of salt. Stir in 1 egg yolk. Add the flour and knead with the dough hooks of the hand mixer. Wrap the dough in foil and chill for 1 hour. In the meantime cut the apricots crosswise in half.
Cut out small hearts for decoration. Finely chop the remaining apricots. Chop the pistachios as well and mix with rum. Roll out the dough thinly on a floured work surface. Cut out round cookies (5 cm Ø). Spread the filling over them. Grasp the edges of the dough with 3 fingers and press over the filling. Place on a baking tray lined with baking paper. Whisk the rest of the egg yolk and spread the biscuits. Place apricot hearts in the middle. Chill for 30 minutes. Then bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 12 minutes.
Grasp the edges of the dough with 3 fingers and press over the filling. Place on a baking tray lined with baking paper. Whisk the rest of the egg yolk and spread the biscuits. Place apricot hearts in the middle. Chill for 30 minutes. Then bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 12 minutes. Remove and let cool off. Dust lightly with icing sugar
waiting time approx. 1 1/4 hours