Grease a square baking tin (approx. 18 x 18 cm) and dust with flour. Drain the cherries. Stir the jam until smooth. Fold in the cherries.
Break dark chocolate into pieces. Dice 125 g butter. Melt both in a hot water bath and let them cool down a little. Finely chop white chocolate. Mix 175 g flour and baking powder. Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see
Pour liquid chocolate butter into a mixing bowl. Add sugar, vanilla sugar, 1 pinch of salt, eggs and flour mixture. Stir briefly with the whisks of the mixer. Fold in white chocolate.
Put the dough into the mould and smooth it down. Spread the cherries on top. Bake in a hot oven for 30-40 minutes. The dough should still be soft so that the cake is nice and juicy. Let it cool down.
Cut off 8 pieces of the brownie. Enjoy the rest of the brownie later or the next day (stays juicy for 2-3 days when wrapped in aluminium foil). Arrange brownies with ice cream and chocolate sauce.