Cream fat, sugar, vanillin sugar and salt. Stir in the eggs one after the other. Mix flour, cornstarch and baking powder and stir into the mixture with milk. Grease a wreath mould (26 cm Ø) or a springform pan with a tube bottom insert (26 cm Ø) and sprinkle with breadcrumbs. Pour in the dough and bake in a preheated oven (electric range: 175 °C/ gas: level 2) for approx. 40 minutes. Let the finished wreath rest in the pan for approx. 10 minutes.
Turn out of the mould and let it cool down on a grid. Cut through the wreath twice horizontally. Wash lemon hot, dab dry and finely grate peel. Halve the lemon and squeeze the juice. Whip the sour cream, 250 g whipped cream, lemon zest and juice, grappa and sauce powder with the whisks of the hand mixer for approx. 3 minutes. Wash and clean the strawberries. Chop half the strawberries, put the rest aside for decorating. Place the bottom layer on a plate and spread with half of the cream. Place half of the chopped strawberries on top and cover with the middle cake layer. Spread the rest of the cream on top, cover with strawberries, finish with the last cake layer and chill. Whip the rest of the cream until stiff and spread it all around the wreath. Decorate with remaining strawberries.
Chop half the strawberries, put the rest aside for decorating. Place the bottom layer on a plate and spread with half of the cream. Place half of the chopped strawberries on top and cover with the middle cake layer. Spread the rest of the cream on top, cover with strawberries, finish with the last cake layer and chill. Whip the rest of the cream until stiff and spread it all around the wreath. Decorate with remaining strawberries. Warm up the strawberry jam and cover the strawberries with it. Decorate with lemon balm if you like