1. Add the margarine and sugar to a large bowl and mix until very light and fluffy. Add the egg and vanilla extract and mix until well combined. Next, add the flour and salt and mix in – the dough will be very soft and sticky. Add the chopped pecans and fold in. Divide the dough into two pieces and shape each piece into a log. Wrap in plastic wrap and place in the fridge overnight.

2. Preheat the oven to 180°C (350°F). Line a baking sheet with baking parchment and set aside.

3. Remove the plastic wrap from the first dough log, but leave the dough on top of the foil. Dust the roll with half of the cocoa powder – works best with a small sieve. The dough log should be completely covered with cocoa powder. Cut the log into (not too thin) slices with a sharp knife and place those slices with some space in between on the prepared baking sheet – the cookies spread a bit. Try not to get any cocoa powder on top of the cookies! Bake the cookies for about 12-14 minutes. Take the cookies out of the oven and let them cool down on the baking sheet for some time, then transfer them to a wire rack and let cool down completely. Repeat the process with the remaining dough.