Preheat oven to 175S. The form was covered with paper and grease with butter.
In a bowl, mix flour, cocoa powder, salt, and baking powder.
Pieces of chocolate with pieces melt the butter in a water bath. Remove the bowl from the water bath, add sugar and mix thoroughly.
Pour the chocolate into the dry ingredients and mix until smooth.
We spread the chocolate batter into the pan and flatten. Bake brownies for 20-25 minutes. Using a wooden toothpick to check availability.
Fully cooled cake cut into neat slices.