Puree garlic, Thai chiles and serrano in blender. Coat fish in lime juice and then in cornstarch. Saute in oil until well browned, about 7 minutes per side. Remove and keep warm. Add garlic mixture to the pan and saute for 30 seconds. Add fish sauce, sugar and basil. Saute for 1 minute. Add water and saute for 1 minute. Cover fish with sauce and serve with rice.