Cut the chives (and / or rocket) into fine strips. Mix all ingredients carefully in a bowl. Squeeze in the peeled clove of garlic and stir again. Chill for 0.5 hours.
There are countless variations of this sauce. Rocket gives a fine, nutty taste, sumac (a level tablespoon) a slightly sour note. It is important that the ingredients do not dominate the yogurt.
If you don`t have to look at your hips, you can use Turkish Süzme as yoghurt. That is a 10% -er that has it in terms of taste.