To create the bitter base I use the following ingredients (ground or chopped):
• gentian root
• quassia bark
For the aromatic base, I use the following (also ground or chopped):
• dried Seville orange peel
• dried lemon peel
• coriander powder
• caraway powder
• aniseed powder
• cassia bark (cinnamon)
Next, I allow both to soak in cheap vodka for differing periods of time. Make sure your vodka isn't complete rotgut. In other words, you shouldn't use a vodka brand that you wouldn't drink straight.
For the bitter blend, I soak the ingredients for two days (you can taste the bitterness when its ready). For the aromatic, I soak things for 10 days and then cook the ingredients for a few minutes in water after removing them from the alcohol. I then add them back to the alcohol and let the mixture sit for another five days. This is akin to squeezing out the last drops of flavor.
Please note that the final infusions contain both aromatic and bitter elements. I just find it useful to separate them for blending purposes. Other bartenders, such as Jamie Boudreau, may separate the blends even further and, in fact, have done some very pioneering work in creating homemade bitters.
With the basic bitter and aromatic infusions in the works, I then create a flavor infusion. Try anything you like: hibiscus, rhubarb, or blueberries, for instance. You can do this by soaking the ingredients in alcohol for an extended period of time or by creating a syrup. For something like blueberries, I don't want them to sit and steep for too long, which would make them become shriveled, pale versions of their fresh selves. So I make syrup from the fresh blueberries with sugar and water and add it to the blended infusions. I might also take some dried blueberries and steep them in the syrup for a touch longer to add depth of flavor. For a heavy aromatic blend, like orange bitters, I use fresh and dried peels from both bitter and sweet oranges and allow them to sit in alcohol for much longer.
The last step is to strain the mixtures and blend them by taste. You can add water and caramel (sugar cooked with a little water in a pan) at this point in the proportions you want. For fig bitters I create a heavier aromatic profile by adding the aromatic infusion to the bitter infusion at a two to one ration and then use dried figs soaked in alcohol for the flavor. Lastly, I add additional water and sugar.
You can order the herbs and spices online at Mountain Rose Herbs. Just remember, whenever I'm asked what the most important ingredient for bitters is I answer, simply: patience. My full recipe is attached. Good luck and please feel free to write your own recipe in the comments!
Recipe: Homemade Bitters