Cut the orange in half, squeeze the juice. Peel and quarter the pears and remove the core. Boil up wine, orange juice, 125 g sugar and spices in a large pot. Simmer pear quarters in the wine for about 10 minutes at low heat.
Turn frequently. Remove the pot from the heat and let the pears cool down in the stock.
Remove the cooled pear quarters from the stock and cut into thick slices. Use the remaining stock for other purposes. Separate eggs. Beat the egg whites with 8 tbsp. water and salt in a mixing bowl until stiff, adding 240 g sugar and vanillin sugar.
Stir in the egg yolks. Mix flour with baking powder and cocoa, sieve onto the egg foam mixture and carefully fold in with the pears.
Pour the sponge mixture into a greased ring cake mould (24 cm Ø; 2 litres capacity) and bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for approx. 50 minutes. Remove from the oven, leave to cool in the mould for approx. 10 minutes, then turn out onto a cake rack and allow to cool.
In the meantime, grate the chocolate into fine rolls with a peeler. Stir cranberries until smooth. Arrange the cake on a plate and decorate with cranberry compote and chocolate rolls.