Place elderberries and 3 cups water (and optional spices) in a medium saucepan.
Bring to a boil.
Reduce heat to a simmer for 30-45 minutes.
Remove from heat and cool.
Carefully mash the berries using a spoon.
Strain the mixture into a glass bowl, making sure you squeeze all of the elderberry juice out. (Use a strainer or cheesecloth.)
In a separate jar, add 1 cup water and 1/4 cup arrowroot. Fasten tightly and shake until the arrowroot is dissolved.
Pour elderberry liquid back into the saucepan and simmer.
Add the arrowroot + water mixture and stir.
Once cool again, add the honey.
Shake before using.