Jin dui, the deep-fried sesame balls Susan Jung's mother can't get enough of

Jin dui - deep-fried sesame balls - remind me of my mother. She loves them so much that one day, when we were visiting San Francisco, she went into every Chinese bakery she could find in search of the best jin dui. By the end of the day she had eaten about six and felt quite ill, because they're so heavy. That didn't put her off jin dui, however, and she eventually taught herself how to make them.

The recipe may seem simple but it took my mother a few attempts before they started turning out round and hollow. You make a sturdy but pliable dough out of glutinous-rice flour mixed with sugar and boiling water. The dough is shaped into balls, which are rolled in sesame seeds. The balls are then fried; they go from being solid to hollow after being pressed against the side of the wok repeatedly with a spatula - this makes them inflate. A good jin dui has a very thin, delicate shell - and the best plain one I've tasted was at Wen Ding Restaurant, in Wan Chai, where the jin dui is about the size of a basketball.

Jin dui are often filled, usually with mashed red bean paste. You put the filling in before they're fried, shaping the dough around it. The best filled jin dui I've had were at Tin Lung Heen, at the Ritz-Carlton - they are small, delicate and stuffed with a delicious salted egg yolk custard.