Training as required (realistically, an hour with a current SEP instructor if you're that current on the turboprop), then a proficiency check.
The PC is officially not a full skill test, in practice the differences are trivial, so you may as well regard it as being one.
The requirement is 12 hours, of which 6 must be PiC and 1 with an instructor; the instructor hour can be for any purpose. But for you, it sounds like the PC is by far the cheaper option.
G