Place a piece of cheesecloth in a colander and pour in the yogurt. Allow the yogurt to drain for several hours. Place the grated cucumber in another colander and allow to drain for 2 hours. Mix together all ingredients exept the additional olive oil and chill. Place in serving dishes and drizzle additional olive oil on top. Serve as a spread for bread or as a dip for vegetables. This is generally served as a first course. Note: Store this dish covered in the refrigerator and it will keep well for 2 or 3 days.
