Wash, halve and stone the plums. Roast almond slivers in a pan without fat until golden brown and let them cool down. Coarsely grate the marzipan. Cream 200 g room-warm fat, 200 g sugar, vanillin sugar and salt.
Stir in the marzipan. Add the eggs one by one. Mix flour, starch, almond slivers and baking powder and stir in. Grease a springform pan (28 cm Ø) and sprinkle with breadcrumbs. Fill in the dough and smooth it down.
Put plums on the dough and sprinkle with 20 g sugar and 20 g fat in flakes. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 1 hour. Leave to cool in the mould on a grid.
Cut the cake into pieces and serve. Whipped cream tastes good with it.