Melt the butter and let it cool down again. Mix 600 g flour, sugar, lemon peel, baking powder and salt. Add eggs and butter and knead into crumbles. Put 1/3 crumble in the fridge for about 30 minutes. Spread the remaining crumbles on a greased baking tray. Press to a smooth base with your hands.
Spread plum puree on top. Mix cold crumbles and 2-3 tablespoons of flour loosely and sprinkle over the plum puree. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) on the lower shelf for approx. 20 minutes. Bake on the middle shelf for another 15 minutes. Let the cake cool down and cut into pieces. Serve with whipped cinnamon cream
30 minutes waiting time