The casual no-frills dining options are endless at Boca de Congrejas in Piñones [1] and a little farther eastward along Carretera 187. In addition to dozens of kiosks selling fritters and coco frio (chilled coconut milk served straight from the shell), there are several casual restaurants selling traditional Puerto Rican cuisine, mostly seafood, for a pittance.
Options include Pulpo Loco by the Sea (Carr. 187, km 4.5, Piñones, 787/791-8382) and The Reef (Carr. 187, km 1, Piñones, 787/791-1973).
Soleil Beach Club (Carr. 187, km 4.6, Piñones, 787/253-1033, www.soleilbeachclub.com [2], Sun.–Thurs. 11 a.m.–11 p.m., Fri.–Sat. 11 a.m.–2 a.m., $10–39) is the closest thing Piñones [1] has to fine dining, but the atmosphere is still appropriately casual, considering its beachfront location. The two-level restaurant serves traditional Puerto Rican cuisine, including pumpkin soup and crab stew, as well as creative Caribbean cuisine like pan-roasted dorado and rock lobster. On weekend nights the place turns into a nightclub when salsa bands and DJs provide the entertainment. The restaurant also offers free transportation to and from your hotel.
Links:
[1] http://www.moon.com/destinations/puerto-rico/east-coast/loiza-and-pinones/sights/bosque-estatal-de-pinones
[2] http://www.soleilbeachclub.com