An Australian student of mine once commented that Bandung's foods seemed to be eclectic. "They are made from this ingredient and that and various mixes and matches from ingredients of the existing recipes."
I didn't realize it then. But I think he's right. And basreng (baso goreng) can be an example. Baso (meat balls) is usually served steamed with noodle soup. Someone must have thought that there must be a new way to serve it. Hence he or she had this idea to fry it and serve it with spicy peanut sauce. And voila, it's basreng, fried meat ball served in or with spicy peanut souce.
Basreng is quite a popular street food. It's usually sold by a street vendor like in these photos.