Separate eggs. Beat the egg whites and 2 tablespoons of water until stiff, adding sugar. Stir the egg yolks into the beaten egg white. Mix flour, starch and baking powder and fold in. Line a baking tray with baking paper. Spread the sponge mixture on half of the baking tray. Fold a bar out of aluminium foil and place it in front of the sponge cake mixture. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 10-12 minutes.
Coarsely chop the chocolate coating and melt it on a warm water bath. Remove the sponge cake, turn it over onto a tea towel sprinkled with sugar, remove the paper. Let the sponge cake cool down. Remove melted couverture from the water bath, take off 1 tablespoon of couverture. Soak gelatine in cold water. Whip 500 g cream until stiff (not too firm) and put it in a cool place. Peel 7 bananas, cut in half lengthwise and sprinkle with lemon juice. Collect the juice. Straighten the sponge cake, place on a plate and cover with a cake frame. Warm up the redcurrant jelly a little, stir until smooth and spread on the cooled sponge cake. Place the banana halves next to each other on the base. Stir about 4 tablespoons of cream into the chocolate coating. Squeeze the gelatine and dissolve. Stir in 3 tablespoons of the couverture, then carefully stir into the remaining couverture. Carefully fold in the rest of the cream, except for 6 tablespoons.
Straighten the sponge cake, place on a plate and cover with a cake frame. Warm up the redcurrant jelly a little, stir until smooth and spread on the cooled sponge cake. Place the banana halves next to each other on the base. Stir about 4 tablespoons of cream into the chocolate coating. Squeeze the gelatine and dissolve. Stir in 3 tablespoons of the couverture, then carefully stir into the remaining couverture. Carefully fold in the rest of the cream, except for 6 tablespoons. Spread the cream on the bananas and smooth it down. Chill the slices for at least 3 hours. Fill 6 tablespoons of cream into a piping bag with star-shaped spout. Loosen the cake frame carefully and cut the cake into 12 rectangular pieces. Peel 1 banana, cut into slices, turn in the lemon juice you have collected and drain. Just before serving, decorate each piece with a cream tuff and 2-3 banana slices. Warm up the chocolate coating again a little and put it into a small piping bag or freezer bag. Cut off a small corner and squirt the chocolate coating in strips over the slices
Spread the cream on the bananas and smooth it down. Chill the slices for at least 3 hours. Fill 6 tablespoons of cream into a piping bag with star-shaped spout. Loosen the cake frame carefully and cut the cake into 12 rectangular pieces. Peel 1 banana, cut into slices, turn in the lemon juice you have collected and drain. Just before serving, decorate each piece with a cream tuff and 2-3 banana slices. Warm up the chocolate coating again a little and put it into a small piping bag or freezer bag. Cut off a small corner and squirt the chocolate coating in strips over the slices