Put the flour in a bowl. Press a depression in the middle, crumble yeast into it. Heat about 100 ml milk and 2 tablespoons sugar. Add to the yeast. Mix with some flour, cover and leave to rise in a warm place for about 20 minutes
Melt 80 g butter, add the rest of the milk. Add the egg, 70 g sugar and Citroback to the pre-dough, knead until smooth. Leave to rise for another 30 minutes
Wash plums, cut in half, stone. Roll out 1/2 dough on a greased, floured fat pan (approx. 32 x 39 cm). Cover with plums
Mix 2 tablespoons of sugar and cinnamon and sprinkle over it. Let the dough rise for about 15 minutes
Roll out the rest of the dough on flour in a fat pan, dust with flour and place on the plums. Press depressions into the dough with fingers
Spread 125 g butter in flakes over it. Mix almonds, 3 tbsp. sugar and vanilla sugar and sprinkle over it. Bake in a hot oven (electric cooker: 200° C / fan oven: 175° C / gas: level 3) for approx. 30 minutes