Separate eggs. Beat the egg whites with 3 tablespoons of water until stiff. Add 125 g sugar, vanillin sugar and salt. Stir in the egg yolks one after the other. Mix flour and baking powder, sieve over the egg cream and fold in. Line the bottom of a springform pan (26 cm Ø) with baking paper. Fill in sponge cake mixture and smooth it down. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 20-25 minutes. Let them cool down. Cut the base twice crosswise.
Place a high cake ring around the lower cake base. Soak 8 sheets of gelatine in cold water. Peel 2 oranges thickly, cut into slices. Squeeze 3 oranges, measure 200 ml juice. Mix juice, 100 ml Campari, sour cream and 100 g sugar. Squeeze gelatine, dissolve, stir into the Campari cream. Chill for about 10 minutes until the cream starts to gel. Beat 500 g cream until stiff, fold in. Spread 1/3 of the cream on the lower base. Spread orange slices on top. Place the second cake base on top. Pour 1/3 of the cream on top, smooth it down. Place the third cake layer on top. Spread the remaining third on the bottom cake layer. Chill for about 1 hour. Soak 4 sheets of gelatine in cold water. Peel 2 oranges thickly, cut into slices. Squeeze 3 oranges to make 200 ml juice. Top up with 50 ml Campari.
Spread orange slices on top. Place the second cake base on top. Pour 1/3 of the cream on top, smooth it down. Place the third cake layer on top. Spread the remaining third on the bottom cake layer. Chill for about 1 hour. Soak 4 sheets of gelatine in cold water. Peel 2 oranges thickly, cut into slices. Squeeze 3 oranges to make 200 ml juice. Top up with 50 ml Campari. Squeeze the gelatine, dissolve. Gradually stir in the juice mixture. Spread the orange slices on the cake. Carefully pour the juice over the cake. Chill for another 2 hours. Remove the cake from the edge. Whip 100 g cream until stiff. Spread the edge of the cake to about 1 cm at the top. Pull a cake comb along the edge
Squeeze the gelatine, dissolve. Gradually stir in the juice mixture. Spread the orange slices on the cake. Carefully pour the juice over the cake. Chill for another 2 hours. Remove the cake from the edge. Whip 100 g cream until stiff. Spread the edge of the cake to about 1 cm at the top. Pull a cake comb along the edge