Coarsely grate the marzipan, add 1 egg, stir with the whisk of the hand mixer until smooth, then stir in the other egg. For the quark and oil dough, stir the quark, milk, oil, salt, sugar and vanillin sugar until smooth. Mix flour and baking powder and knead into the quark mixture. Roll out the dough on a floured work surface to a thickness of approx. 5 mm. Cut out 12 circles (9 cm Ø).
Line 2 baking trays with baking paper and place dough circles on top. Spread circles with the marzipan mixture. Bake in the preheated oven (electric range: 200 °C/ convection oven: 175 °C/ gas: level 3) for 12-15 minutes one after the other. Let the tartlets cool down. Wash and halve the plums, remove the stone. Cut plums into slices. Cover the tartlets with them. Bring jam to the boil in a small pot, simmer for about 2 minutes. Remove from heat and spread on the tartlets. Roast the flaked almonds lightly in a pan without fat.
Cut plums into slices. Cover the tartlets with them. Bring jam to the boil in a small pot, simmer for about 2 minutes. Remove from heat and spread on the tartlets. Roast the flaked almonds lightly in a pan without fat. Let it cool down a little bit and sprinkle the tartlets with it. Serve dusted with icing sugar