Combine the ingredients in a mortar and grind to a coarse powder and then pack in a percolator, or other suitable maceration vessel. Pass the alcohol through the percolator over a period of 48 hours to create the Hartz Bitters stock essence. If macerating, allow the mixture to macerate for 2 days with occassional agitation, then filter and reserve the liqud.
To make the Hartz Aromatic Bitters from the above essence, take 1 oz of essence and combine it with 1700 ml of 25% alcohol, 300 ml of 60% simple syrup.
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