Grease the oven pan and sprinkle with breadcrumbs. Melt 100 g butter. Crumble the rusks and mix with the melted butter. Put the mixture into the fat pan, press it smooth and put it in a cool place.
Cream 150 g butter, sugar and vanillin sugar. Add cream cheese, sour cream, quark, lemon peel and eggs and stir until smooth. Mix flour and starch and also stir in. Spread the mixture on the rusk base and smooth it down.
Bake in the preheated oven (electric cooker: 200 °C/ convection oven: not suitable/ gas: level 3) for approx. 10 minutes. Switch the temperature down (electric oven: 100 °C/ convection oven: not suitable/ gas: level 1) and bake for approx. 1 1/4 hour.
Let the cake cool down. Divide the cake into 12 squares and divide them diagonally again. Wash lemon and lime, dab dry and cut into very thin slices. Decorate cake pieces with it.