Melt the chocolate with the butter in a double boiler. In the meantime, stir the eggs and sugar with the electric mixer until creamy. Mix the flour, baking powder, cocoa and nuts separately. Tip: I grind whole nuts fresh, toast them briefly in a pan without fat until they smell fragrant.
Add the liquid chocolate butter to the egg / sugar mixture with a spoon and stir. Slowly add the dry ingredients and stir in. Chill for 1 hour.
Preheat the oven to 180 ° C. Cut off the dough, shape into balls with floured hands or - like me, with an ice cream scoop and place on a baking sheet lined with baking paper.
Bake for 10-15 minutes. The pastry should still be a little soft, it will be even harder after cooling. Dust with icing sugar while it is still hot.
The balls taste best fresh, but they can also be kept in a cookie jar for a few days.