Very, very chocolate! You can use cherries, cranberries, raspberries. The taste is very intense.
Soak the berries in alcohol for at least an hour. Drain, cut into small pieces.
Coarsely chop the chocolate and, stirring occasionally, melt in a water bath. Cool for 5 minutes. Line a 20 x 20 cm square dish with baking paper. Preheat oven to 175 ºC.
In a deep bowl, beat sugar with butter and vanilla with a mixer until a fluffy light consistency. Whisking continuously, add eggs one at a time and melted chocolate. In a small bowl, mix flour, baking powder, cocoa powder and prepared berries.
Add the flour mixture in two additions, mixing gently and thoroughly with a wide spatula after each addition.
Pour the batter into the prepared pan, flatten and place in the preheated oven. Bake for 25 minutes. Cool the brownies in the mold for 20-30 minutes. Cut into 9-12 portions. Decorate with cocoa powder if desired.