Jian dui originated as a royal food in Chang'an, the Tang-dynasty capital.
The pastry was reportedly known then as lüdui (碌䭔). Its early association with Chang'an places the origin story in the Tang dynasty, when the city—modern Xi'an—served as the empire’s principal capital and a major center of court life, trade, and cultural exchange.
Jian dui is made from glutinous rice flour, coated in sesame seeds, and fried until the outside becomes crisp while the interior stays chewy. The expanding dough creates a characteristic hollow space, usually filled with lotus paste or sweet bean paste. Regional versions later developed different names, including matuan in northern and northwestern China and mayuan in the northeast.
The pastry spread southward as populations moved from central China after the An-Shi Rebellion. It eventually became part of southern Chinese cuisine and is now familiar as a sesame ball in dim sum restaurants. Luoyang was also an important Tang capital, but the origin account specifically identifies Chang'an, so the alternatives are not interchangeable here.