Yang's Fry Dumplings or 小杨生煎 is a chain of super-cheap dumplings and soups that you can find all over Shanghai. We visited the one inside Reel Shopping Center in JingAn (Metro stop JingAn Temple, lines 2 & 7).
4 dumplings cost 6 RMB, less than 1 euro, the soup is 8 RMB. Although the menu here is simple, there are pictures you can point at to order.
Surely the cheapest meal we've had, the dumplings are great, perhaps if they weren't so boiling hot they would be excellent. The location at Reel mall is super conveninent if you're staying in the area, especially because you can sit down and enjoy your dumplings, not like in many other branches where you eat standing up. It's also nice to walk around the food court to see the different food options (sushi, macarons, cakes, etc.) - the mall upstairs however was empty, lots of super expensive stores but almost no people around.
Yang's Fry Dumplings @ Reel Kitchen
1601 Nanjing West Rd - Level B2, Jing'an, Shanghai
Chinese address: 南京西路1601号