We asked the hotel where we can have some local special food, and the hotel told us to go to "Heng-Mien". It was a busy restaurant with lots of locals. The price was cheap at Rp16,000 per person for the set menu. The food came as soon as we sat down.
The special local food that we looked for were RW (dog), Paniki (bat), Babi Hutan (boar), snake, and I forgot the other one.
The day we went to Heng Mien, they only have RW. (Top left dish on the picture.) I did not really like the food there, because all the ingredients were mashed together, and everything is just dark colored. The presentation has a long way to go. (But at HK$16 per person all-you-can-eat, I probably shouldn't expect too much.)