Place a cake ring (26 cm Ø) on a cake plate. Lightly brush the base with oil. Put meringue in a freezer bag and crumble coarsely with the cake roll. Finely chop the chocolate and melt it on a hot water bath. Mix the meringue and chocolate well and press it onto the base with a spoon.
Put it in a cold place. In the meantime soak gelatine in cold water. Mix ricotta, yoghurt and sugar. Warm up the lime juice and remove from the heat. Squeeze 8 sheets of gelatine well and dissolve them in it. Stir gelatine with 2-3 tablespoons of cream until smooth. Mix with the remaining cream and refrigerate for about 8 minutes. Puree raspberries and vanilla sugar, warm up and remove from the heat. Squeeze out 2 sheets of gelatine well and dissolve in it. Chill for about 5 minutes.
Mix with the remaining cream and refrigerate for about 8 minutes. Puree raspberries and vanilla sugar, warm up and remove from the heat. Squeeze out 2 sheets of gelatine well and dissolve in it. Chill for about 5 minutes. Whip the cream until stiff and fold into the ricotta yoghurt cream. Place 2 layers of cream and raspberry puree on each base. Use a fork to draw through the cake like a marble and chill it for about 4 hours. (Important note: do not put it in the fridge for too long, because the meringue draws moisture!!) Serve the cake decorated with meringue tuffs and raspberries