Wash the lemons hot, grate them dry and grate the peel of 1 lemon thinly. Halve the lemon and squeeze it. Cream fat, 350 g sugar, vanillin sugar and salt with the whisk of the hand mixer. First stir in grated lemon peel, then add eggs one after the other. Mix flour and baking powder and stir in alternately with the sour cream.
Grease the fat pan of the oven (approx. 32 x 39 cm) and dust with flour. Add the dough and smooth it down. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 25 minutes. Cut 1 lemon into thin slices. Bring 100 g sugar, lemon juice, lemon slices and 150 ml water to the boil and simmer for 2-3 minutes. Set aside. Remove the cake from the oven and brush with half of the syrup. Allow to soak in and repeat the process. Spread lemon slices on the cake.
Bring 100 g sugar, lemon juice, lemon slices and 150 ml water to the boil and simmer for 2-3 minutes. Set aside. Remove the cake from the oven and brush with half of the syrup. Allow to soak in and repeat the process. Spread lemon slices on the cake. Let the cake cool down
Waiting time approx. 1 hour