4 quarts filtered water
1 cup natural cane sugar
5 tea bags organic, black tea
½ cup finished kombucha
1 kombucha mushroom (s.c.o.b.y. Symbiotic Colony of Bacteria and Yeast)
Bring one quart of the water to a boil. Remove from heat and stir in sugar until dissolved. Steep tea bags for 15 minutes. Remove tea bags. Pour this mixture and remaining water into a clean wide mouth, gallon size glass jar.
Add ½ cup kombucha from a previous batch. Place the mushroom, dark-side down, in the liquid.
Cover with cheese cloth and place in a warm, well-ventilated place, out of direct sunlight.
The kombucha will be ready in 6-12 days depending on the temperature. It is ready to drink when the liquid is relatively translucent and a ‘baby’ kombucha mushroom has formed above the mother. Start tasting it daily after 1 week. As soon as you like the flavor, you can bottle it in smaller glass jars or repurposed glass bottles. Store finished kombucha in the fridge. Reserve the mother and about ½ - 1 cup of kombucha to make the next batch of kombucha. Give extra mothers away or compost them.
Here is one source online where you can buy a kombucha mushroom.