Chop the bananas into small pieces.
Melt the dark chocolate and butter together in a double boiler.
Add sugar and eggs to the melted chocolate and mix well.
Add flour, cocoa powder, and salt, then mix until combined.
Add the bananas to the batter and mix.
Pour the batter into a mold and smooth the top.
Bake in a 180°C oven for 25-30 minutes.