Clean and wash the plums, carve lengthwise and stone them. Cream fat, 200 g sugar and salt with the whisk of the hand mixer. Stir in the eggs and egg yolks bit by bit. Mix flour and baking powder and stir into the fat egg mass with the milk.
Fold the Amarettini into the dough. Put the dough on a greased fat pan (37 x 32 cm) and smooth it down. Spread the plums on top. Bake the cake in a preheated oven (electric: 200 °C/ gas: level 3) for 20 minutes.
Beat egg white and lemon juice until very stiff, mix remaining sugar, vanillin sugar and cinnamon and finally let it trickle in. Pour meringue mixture into a piping bag with star-shaped spout and spray 20 curls onto the cake.
Bake the cake for another 20-25 minutes. Let it cool down on a cake rack and dust with icing sugar. Makes about 20 pieces. Serve with vanilla ice cream.