French beef, Costa Rican coffee beans and Australian lobsters might be food industry purchasers' favorites at the ongoing China International Import Expo, but traditional Shanghai snacks are the delicacies finding their way into the stomach of the thousands of exhibitors from around the world.

Shanghai Specialty Snack Restaurant, a pop-up in the center square of the National Exhibition and Convention Center (Shanghai) during the six-day event, has enjoyed unprecedented popularity among all the expo's participants.

"We are selling dumplings like hot cakes," said Wang Hong, director and co-founder of Wanyou Market, which is operating the food hall.

According to Wang, the municipal government commissioned the Shanghai-based startup to operate at the expo, and sales in the first four days surpassed all estimates, reaching 600,000 yuan ($86,000).

Daily turnover could reach as high as 250,000 yuan a day on the last two days of the expo, which are open to the public, she said.

"The figure could actually go much higher. But everything is made to order here and there is a capacity ceiling of 20,000 servings every day," she added.

Covering 2,200 square meters, the restaurant, open from 9 am to 7 pm nonstop, is separated into two pavilions. One pavilion is dedicated to prepackaged snacks that double as souvenirs. The other consists of 24 of the city's most well-known eateries, which offer dim sum and appetizers in a set menu format.

A dozen chefs and a handful of culinary artisans are working on site to offer Shanghai's signature bites, such as xiaolongbao (soup-filled dumplings), shengjian (pan-fried dumplings with a golden crispy layer at the bottom) and vegetarian dishes.

"We arrive every day around 6 am. We work much longer hours and wrap dumplings much faster than usual, but have still been unable to feed everyone," said Sun Weiming, head chef of Nanxiang Xiaolong, one of Shanghai's most coveted eateries.

Located inside the city's famous tourist site Yu Garden, it dates back to the 19th century. Sun has worked at the eatery since the age of 18. The 34-year-old said this is the first time the restaurant has served dumplings outside its usual location.

Together with Sun's team of six chefs, the restaurant is staffed by some 200 experienced waiters handpicked from 24 reputable restaurants across the city, as well as another 40 bilingual volunteers.

A meal at the restaurant costs around 50 yuan. In order to cater to an international audience, more beef dishes have been added to the menus, as Chinese menus are usually more pork-dominant.