Soak kidney beans in water overnight. After soaking for 6 hours, kidney beans must be cooked for 1.5-2 hours. If you soak kidney beans for 12 hours, their cooking time is reduced to 45-60 minutes. After cooking, the beans can be further processed.
Preheat the oven to 180°C top/bottom heat and line the brownie pan with baking paper.
Place all ingredients except the dark chocolate in the container of a kitchen blender or use a bowl and the blender. First work everything into a smooth mass at a lower and then at a higher level. Now add 100 g of the chopped chocolate. Fold the chocolate pieces into the dough and then fill the dough into the prepared baking tin.
Sprinkle the rest of the chocolate over the dough and bake the brownies in the preheated oven for about 30 – 35 minutes, until no more dough sticks to the toothpick when you test with the sticks.