Are there any common and/or traditional Turkish dishes which are vegan?
There's a dish called Yelanchi, which is stuffed grape leaves. I was told Yelanchi comes from Turkish word meaning liar, since ordinarily the (dolma) stuffing would contain meat. However, this variation is vegatarian/vegan and includes rice, herbs and even walnuts in some recipes.
Here's a link to a recipe - http://www.mission-food.com/2010/12/yalanchi-vegetarian-stuffed-grape.html