Although it’s not exclusively vegetarian, La Cedre in downtown Zurich has extensive vegetarian offerings on the menu. I loved the hummus, fresh artichoke in garlic sauce, spinach pies, eggplant salad… pretty much everything I tasted (and since some of the people at our table got a multi-dish tasting menu, I sampled a lot of dishes).
If you’re in the mood for Middle Eastern food (and belly dancers) in Zurich, I can definitely recommend this place. The only drawback I found was the high prices, but then again everything in Zurich is overpriced, so it wasn’t exactly shocking.