Preheat oven to 180 degrees C. Grease baking trays.
Cream the butter, white sugar, eggs and vanilla.
In a separate bowl, stir the flour, 2/3 cup cocoa, baking powder, bicarb soda, salt and spices. Add flour mixture to butter mixture. If too sticky add more flour, if too dry add a little milk. Add nuts and mix with hands. Must be of consistency to roll into little 3cm balls.
After you have dough to handling consistency by adjusting it with either the flour or milk, roll into little balls, place on the baking tray and bake for about 10-12 minutes, biscuits should be firm. Do not overcook. Remove from oven, let rest on the tray for a few moments and remove to wax paper. When cool, ice with cocoa glaze.
To Make Glaze: Combine icing sugar and 1/4 cup cocoa then add about 1/2 cup (125ml) milk. Consistency should be of a glaze. Pour small amount of glaze over each biscuit (about 1 tsp.). Decorate with sprinkles while glaze is still wet.