Puree all of the ingredients, including the tomatillo juice, in a blender or food processor.
If using fresh tomatillos add ¼ cup white vinegar and you may require some salt to taste.
Store in a tightly sealed container in the refrigerator for up to 4 days.
Notes
Variation: If you would licit try a smoky tomatillo salsa, substitute chipotle peppers for the jalapeño peppers. Chipotle peppers are smoked jalapeño peppers in a spicy adobo sauce and can be found canned in the Mexican foods section of your grocer.