Preheat oven to 350 F. Line the loaf pan with baking paper
In a bowl, mix flour, cocoa, baking powder and salt
In another bowl, cream the butter with sugar and vanilla sugar
Beat eggs well. Add to creamed butter
Add milk and mix well
Add dry ingredients and mix until you get a smooth batter
Pour the batter in the loaf pan
Top with raspberries, gently pressed into the batter until completely covered
Bake for about 50 minutes or until a toothpick inserted in center comes out clean. If you find that it starts to burn on top, cover the cake with aluminum foil. Once done, leave to cool for 10 minutes before taking out the loaf pan