Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). Grease a springform pan (26 cm Ø) with some oil and dust with flour. Chop 50 g chocolate and melt in a hot water bath.
Peel and quarter the pears and remove the core.
Separate eggs. Refrigerate the egg whites. Beat the egg yolks and brown sugar with the whisks of the mixer until creamy. Stir in melted chocolate. Add the soy drink and 5 tbsp. oil while stirring. Mix 200 g flour, baking soda and cocoa and fold in quickly.
Smooth the dough in the form. Spread pear quarters on top. Bake in a hot oven for 50-55 minutes.
In the meantime, break 25 g of chocolate into pieces and melt in a hot water bath. Beat the egg whites until stiff, letting white sugar trickle in. Finally stir in vinegar.
Remove the cake from the oven after about 40 minutes baking time. Spread the meringue mixture with a spoon, while lifting up small peaks. Drizzle chocolate over it and whirl it in with a fork. Continue baking the cake.
Let it cool down on a grid.