Pani puri is the original chef-suggests-you-eat-this-in-one-bite snack.

Fragile, time-sensitive and extremely delicious, the Indian street food involves a tiny hollow crisp filled with soft, spicy half-mashed vegetables, finished with a glug of cumin- and tamarind-spiked water. The shell can barely hold. You have to manage it in one go, immediately, before you lose the effect of delicate crunch over a cool rush of tang and spice. 

It's just one of many dishes from the chaat family, fast food made-to-order on the street and in casual cafés across India, and soon you'll be able to find it at Kailash Parbat, the Murray Hill outpost of the Indian vegetarian chain. For now, a server explains, they're having a hard time sourcing puffy shells that meet their standards.

In the meantime, you can get other goodies from the chaat bar, which runs along one side of the dining room and is full of mise: battered and fried cauliflower and chiles; mashed potato and crunchy chickpea ribbons; tamarind chutney and yogurt; chopped raw onion, tomato, cilantro and tubs of brightly colored chile powders. It's a bigger, glassier version of what you might see a vendor carrying around a train station in Mumbai.

Clockwise from top: Finishing the chaat platter | Masala chai | Flat crisps ready to load

There's a fine dahi vada made from tender fried lentil cakes, soaking in green chutney under a cool sheet of yogurt ($7), and the potato-stacked crisps known as batata puri ($7). Everything has varying levels of crunch and tang, but the cooks do have a light touch, so ask for more heat if you need it—bhel puri, a puffed rice extravaganza, is better when it's extra spicy ($7).

The chain was founded in the 1950s by two pani puri–slinging brothers and has grown to many locations all over India. Though it's not a showcase for the country's most refined or complex regional flavors, it's a reliable place to drop in for a pot of sweet cardamom-scented black tea ($3.50) and some cheap, delicious snacking.

And that's what everyone here seems to be doing on a weekday afternoon. A young Indian man dressed like a lumberjack eats lunch alone by the window, a big plate of rice and dal, the yellow lentils cooked northern-style here, with plenty of garlic and cumin ($11.50). Young parents with two adorable, squeaky-voiced kids share sandwiches and plates of fried paneer. By the window looking onto 27th Street, a couple of women dining on their own polish off their lunch specials—hot, charred bread and vegetable curries in clay pots ($12.50)—with one hand, while typing on their phones with the other.

It's certainly a good place for a fast working lunch: The chaat tends to be ready and at the table within just a few minutes. If you're doing it right, the chutney and yogurt-soaked snacks will be gone just as quickly.