G'day, sport. For me, pre-cooked chicken is
not essential; I regularly make my curries these days using fresh (free-range) chicken and have not for a long time felt the need to pre-cook it. I
believe that pre-cooking is simply a restaurant convenience, to allow dishes to be prepared faster (and arguably, more consistently) than if fresh chicken were used, with the added benefit that pre-cooked chicken can be kept at room temperature for somewhat longer than fresh chicken without the food hygiene inspector throwing a wobbly. Can't help with a recipe involving spiced oil (but see the
recent debate on the topic); for a simple and fool-proof recipe using base gravy, perhaps see my "Phil's phoolproof curry"
recipe which
does use pre-cooked chicken.
** Phil (CSIRO/DITMELB, Melbourne 1987).