Wash the berries, drain them, strip them from the panicles and mash them lightly with the rock candy. Let stand in a bowl overnight.
The next day, crush the cloves and the cinnamon stick in a mortar and fill a large, bulbous bottle with the mountain ash and the drawn juice. Pour on the grain or brandy. Close the bottle tightly and put it in a bright place, but not in direct sunlight. Let the mixture stand for 3 months, shaking frequently.
Strain according to the above method. Not too bright for 8 months.