1. line the bottom of the cake springform pan (26 cm ø) with parchment paper. Separate the eggs. Whip egg whites, 2 tbsp. cold water and salt until stiff, adding 50 g sugar and 1 packet vanilla sugar. Beat in egg yolks one at a time. Sift flour, cornstarch and baking powder on top, fold in. Spread into the form. Bake in a hot oven (electric oven: 175 °C / convection oven: 150 °C /gas mark 2) for about 12 minutes. Cool.
2. Soak 10 sheets of gelatine in cold water. Stir yogurt, 100 g sugar and 2 packets vanillin sugar. Squeeze gelatin, let it melt at low temperature. Stir in 3 tbsp yogurt, then stir into remaining yogurt. Chill until it begins to gel (approx.
half an hour). Drain pears well, cut into wedges. Whip 500 g whipped cream until stiff, fold into yogurt.
Place a high springform pan rim (approx. 8 cm high) around the sponge. Place a preserving jar (approx. 10 cm ø) in the center with the opening facing up. Spread the pears evenly over it. Spread the yogurt cream on top.
Leave to cool for approx. 3 hours.
4. Soak 4 sheets of gelatine. Heat the milk (do not make!). Break 100 g of chocolate into pieces and let it melt while stirring. Cool down a bit. Squeeze gelatine and let it melt. Cool for approx. 10 min. Whip 500 g whipped cream until stiff, fold in. Pour lukewarm water into the glass. Pull out the glass after about 5 minutes. Pour chocolate cream into the hole and onto the yogurt.