Place all ingredients except the chopped cilantro and daikon or fennel in blender or food processor; add 2 tablespoons water and process until very smooth. Refrigerate at least an hour to let flavors develop. Stir in chopped cilantro.
The dip may be made up to 2 days ahead. Just before serving, sprinkle with the daikon or fennel. Serve with an assortment of raw vegetables.