Sort blackberries. Pour the apricots into a sieve and drain. Put the apricots into a high mixing bowl and puree them with a blender. Mix corn flour and baking powder. Wash lemon hot, grate dry, grate peel thinly.
Halve the fruit and squeeze the juice of one half.
Beat the eggs, vanillin sugar and sugar with the whisk of the hand mixer until frothy. Stir in apricot puree, oil, lemon juice and zest. Fold in the maize flour mixture. Put the dough into the greased fat pan of the oven and smooth it down.
Spread the blackberries on the dough.
Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for approx. 30 minutes. Remove the cake from the oven, let it cool down, dust with icing sugar and cut into pieces.