This place had some tasty buffet items, many of which are vegan. It is walking distance from the main beach, which is convenient. It seems to cater mostly to locals and was packed when I went (good to see!)
If you have a long bus ride coming up, make yourself a takeaway meal here as well before you leave.
There is also a health food shop next door which may or may not be part of the restaurant, that sells many veggie products including soymilk chocolate!
Cons: May have to wait for a seat!