3 of my faves are on soi Lengkee just around corner from Bukhao, the first one on south side of soi (going towards 3rd Rd) does a great khao man gai for 40 baht (can get chicken fried or poached as usual) and there is a noodle soup stall directly across from it also very cheap and beside that there is a great donair place for 60 baht