Vaishali is legendary and known to all the people of Pune and many people outside of it, as well. It's an institution. It's a simple cafe with indoor and open-air seating and classic South Indian dishes like masala dosa, idli sambar and uttapam. Their dosas are without a doubt the best I've ever had, and I've lived and traveled all over India and had many dosas in the US as well. My parents are South Indian and I can honestly say that Vaishali cannot be beat, not even in the deep south of India. Also make sure to try some of their appetizers like veg. cutlet and vada. Their juices are also fresh and tasty.
The bulk of the menu is naturally vegan, especially staples like masala dosa and uttapam. Non-vegan items will typically be labeled with the words "butter" or "ghee." If you're still unsure, ask the waiter or someone nearby if a dish is traditionally prepared with dairy products (either milk, cream, butter, ghee, yogurt or milk curds).
Vaishali is almost always full, and you'll always have to wait for a table. That said, turnaround is fast and you never have to wait long. The service is brisk and efficient, though not necessarily super-friendly. Vaishali attracts a mixed crowd, from old men who sit, reading the newspaper and drinking coffee, to college students, to in-the-know foreigners, to families.