Add the chopped onions, garlic, grated horseradish, grated ginger, cayenne, and turmeric (if using) to a half-gallon-sized mason jar.
Add enough apple cider vinegar to cover everything by about 4-6 inches.
Place a lid on the jar and shake it very well to combine.
Label and place in a warm spot or sunny ledge for 4-6 weeks. Shake it every day or so, which will help the vinegar to draw the properties out of the ingredients.
Strain the fire cider through a fine mesh strainer, or a colander lined with cheesecloth.
Compost or discard the solids.
The remaining liquid is your finished fire cider. Add enough warmed honey so that it tastes sweet enough to drink, but still a little zingy and spicy!
Transfer the fire cider to clean bottles and label them with the name, date, ingredients, and instructions.
Store at room temperature for 2-3 months or in the refrigerator for up to 6 months.
Take 1-2 teaspoons daily as a tonic, or 1-2 tablespoons at the first signs of a cold. If seeking help with a cold, take every 3-4 hours until your symptoms subside.