Beat the warm fat, sugar, vanillin sugar, bitter almond flavour and salt with the whisk of the hand mixer until foamy. Stir in the eggs one by one. Add flour, almonds and baking powder and mix.
Grease a springform pan (26 cm Ø) and sprinkle with semolina. Fill in the dough and smooth it down. Wash plums, dab dry, halve and stone. Put the plums on the dough and bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 1 hour.
Remove the cake from the edge with a knife and let it cool down on a grid. Decorate with roasted almond flakes. Whipped cream tastes good with it.