, you've got 2 I'm going to recommend... All Taiwanese style/new style veggie... haha, but they are quite tasty compared to the others, I think I like 雅室友more...
Traditional one you can visit the temples...
When I see emailyahoo reply "All" I know he's not very familiar with what "veggie" can cover...
雅室友素食 is bad
very bad
very expensive for mediocre food
i'd suggest eating western vegetarian food. variety and taste, as well as price are more reasonable that ALL chinese veg food.
one very good and popular one is the foundation on kingsway and main
another one that is also very popular for burittos is called budgies burittos also on kingsway and main. on the same block there's another restaurant that serves veg food called wallflower, which is not bad too.