Step 1

Cook: Add berries, water, and sugar to a medium saucepan. Cook, uncovered, over medium heat until berries burst, mashing them a bit to form a thick liquid (should take about 10 minutes). Let cool to room temperature (to quicken this up, set pan in a sink full of cold water).

Step 2

Bottle: Evenly distribute berries and vanilla into fermentation bottles. Pour in first fermentation kombucha, leaving 1 to 2 inches free at the top.

Step 3

Ferment: For 3 to 10 days, until it reaches the carbonation level you like.

Step 4

Enjoy: Chill in the fridge before serving, optionally straining out the fruit fibers.