Cover cashews with water and soak while you prep other ingredients. (you can soak for up to 12 hours before you use them)
Add cold water, salt, vinegar and lemon juice.
Pour off all water from nuts, and place in food processor.
Puree for 3-4 minutes or until completely smooth and creamy in consistency.
Use in any recipe that calls for sour cream.
stores in the fridge, in an airtight container, for up to a week.