Melt the butter in a small pan. Add the chocolate and stir to melt, allow to cool slightly. Mix the eggs, sugar, vanilla sugar and salt in a bowl. Add the chocolate mixture, mix. Combine the flour and baking powder, mix in, then carefully mix in the raspberries. Transfer the brownie mixture to the prepared tin, smooth down.
Approx. 25 mins. in the centre of an oven preheated to 180°C. The brownies should still be gooey inside. Allow to cool slightly, cut into squares in the tin while still warm.
Bring the raspberries and sugar to the boil in a small pan while stirring. Remove the pan from the heat immediately, allow to cool slightly. Place the warm brownies on a rack or plate, cover with the glaze, leave to cool.