Defrost puff pastry slices at room temperature. Drain apricots and cut into slices. Grease the cake tin (10 cm Ø). Cut the puff pastry slices in half, place one half in each mould and press lightly.
Cut off protruding edges. Prick the dough several times with a fork. Spread apricot slices on top. Dust the tartlets with icing sugar and bake in the preheated oven (electric cooker: 250 ° C/ gas: level 4) for 10-15 minutes.
In the meantime, for the sauce, melt sugar in a pot and brown lightly. Mix 2 tablespoons of milk and starch. Gradually add the remaining milk to the sugar and bring to the boil once. Stir in the starch and bring to the boil again while stirring.
Sprinkle the tartlets with pistachios. Arrange one tartlet each with some sauce and possibly mint leaves on a dessert plate.