- 4 cups finished water kefir (grains removed)
- 1 tablespoon vanilla extract (or to taste)
- Combine ingredients in a jar with an airtight lid.
- Let sit at room temperature for 2 days.
- Refrigerate after 2 days. It will keep for quite awhile, but will taste best when consumed within a couple of weeks.
*Caution- when doing a second fermentation, contents can sometimes become a bit explosive. If it's excessively warm, or if there isn't enough headspace, your jar can blow its top. Monitor the lid- if it starts to bulge a bit, open & close the lid to burp the excess gases. A kitchen towel draped over the top can be added insurance in case of an eruption.