Cover the raisins with hot water, soak for about 30 minutes. Orange, except for 1-2 slices for decoration, chop roughly. Separate eggs. Whisk egg yolks and sugar with the whisk of the hand mixer until white-creamy. Fold in ricotta and almonds. Drain raisins, squeeze. Stir in raisins, chopped oranges, vanilla sugar and lemon zest.
Beat egg whites until stiff, fold in. Grease a springform pan (24 cm Ø) and sprinkle with breadcrumbs. Pour in the mixture and smooth it down. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 45 minutes (test with sticks). Take out the cake and let it cool down on a cake rack. Cut the remaining orange into pieces. Remove the cake from the tin, cut it into pieces, arrange it on a plate and decorate with orange pieces
Waiting time approx. 1 hour