The Jaewhon restaurant by the Bueng Kan Nakhon reservoir, right next to a PTT gas station, offers friendly prices. A small set is just 29 baht. Yesterday, I went there with 7 people, and it only averaged 170 baht per person! The broth was rich and flavorful, and the dipping sauce was deliciously spicy. We could eat continuously without any delays, even though the place was crowded.