Mix the solids in a mortar and reduce to a coarse powder. Extract using slow percolation or maceration over a period of days.
To make the bitters, mix 1 fluid ounce (30ml) of this extract with 450ml of 40% alcohol. To make Berlin Wine-Bitters, replace the alcohol and water with sweet catawba or sherry wine.
by Darcy O'Neil :: [Bitters]
Each region in Germany had a local bitters, and this is a recipe for one in the Berlin area.