This is a cashew version of the ranch dressing I have posted elsewhere on my site. If you're avoiding oil, this is the perfect ranch dressing for you.
To a high speed blender, add the cashews, soy milk, and vinegar. Blend until very creamy with no grit. Pour the mixture into a sealable container, add the seasonings, and shake or stir. Allow the ranch to chill for at least an hour before using.