Paani Puri
Also known as "gol gappa" or "gup chup". It comprises a round, hollow puri, fried crisp and filled with a mixture of water, tamarind, chili, chaat masala, potato, onion and chickpeas. It is small enough to fit completely in one's mouth.
The name gol gappa refers to the fact that crisp sphere (gol) is placed in the mouth and eaten (gappa) at one time, without biting. Urdu comes from the Hindi word for water and puri (or poori) is the name of an Indian bread made by frying dough in oil.
Typically, panipuris are served with 5–8 in a portion on a triangular "plate" made from dry sal leaves. Some places offer panipuris pre-made into a whole plate, but the popular way for them to be served is one at a time from a road-side vendor. Customers hold a small plate and stand around the server's cart. The server then starts making one panipuri at a time and gives one to each individual. Panipuri servers have to remember each customer's preferences such as sweetened pani, more filling or extra onions, for example. The server must also keep count of how many panipuris each person has had. Panipuri servers are renowned for remembering choices and numbers served, even when serving an entire crowd.
Traditionally, panipuris are eaten by placing the entire puri into the mouth in one go and biting into it. This releases a barrage of different tastes. Panipuris may be finished off with a cup of the pani, sweetened or made tarter to taste.
http://en.wikipedia.org/wiki/Panipuri