Need help searching for this good

This is some kind of bun I ate in HK but can't remember where exactly, otherwise I would check the menu online but here we are. So this was typically a hot dog shaped bun, but it seems like deep fried instead of baked and there's something like char siu instead of sausage. Also added pieces of fresh cucumber. That's all I remember but the taste was amazing, I would like to recreate it at home