My favorite would be Pappi's , the Lions club has a bar b q on Fri. nites for under $5 us. I think, very good chicken, located right behind the Mayan Princess,center of town. I also like The Reef Rest. Ali Babas is good also, located near the Air Strip, You'll see their chickens hanging in the window.
Try the street vendors for the quick cheap taste of the local flavor.
I've been diving S.P. for about 20 yrs. so p.m. me if you want,I'm there Feb. also.