Mix the oil, sugar, eggs, water, flour, baking powder and vanilla sugar into a batter, place on a baking tray and bake at 175 ° C for about 20 minutes. Let cool down.
Spread the drained mandarins on top. Thicken the mandarin juice with cake glaze and pour over it.
Whip the cream and sour cream separately with the cream stabilizer or preserving sugar until stiff. Mix in a large bowl and spread over the cake. Mix the cinnamon and sugar and sprinkle with them on the cake.