These cookies are very easy and quick to prepare, and it's great to involve the children in making them - roll the balls and put them on a baking sheet.
Beat butter with sugar and vanilla in a mixer. Add the egg, then the flour sifted with the baking powder and beat again.
Add nuts, cocoa and chocolate. Turn on the mixer for a few seconds to quickly mix everything. Send the dough to the refrigerator for 30 minutes. Preheat oven to 180 degrees.
Roll into balls and place them on a baking sheet. There should be a distance of about 2 cm between the balls. Bake for 15 minutes. Cool on opposite side.