Place butter with sugar in a small pot. Melt them over low heat by stirring constantly.
Add cocoa powder and continue stirring, try to blend powder evenly in the mixture.
In the end, pour milk. Stir until you combine all the ingredients and the mixture is smooth.
Divide cookies into 2 even parts. One-half blend into fine crumbs. The other half break into big chunks of cookies.
Combine chunks of cookies, crumbs and chopped walnuts in a bowl.
Combine dry ingredients with the mixture from the pot.
Stir mixture until well blended until it becomes one batter.
Transfer the mixture onto the plastic wrap and roll it into salami like form (any form you would like round, square). Check that the plastic wrap is tightly wrapped.
Leave it in the fridge for 5-6 hours. Make sure that it is firm before you are going to cut it. Remove wrap before cutting into thick cookies. Enjoy your meal!