You'll have to take one of the CFI practical tests as specified in 61.183.
As for the having to do it with a FSDO inspector or DPE, I'm no longer sure how this works. I know that some areas in the U.S. (Ft. Lauderdale FL. FSDO jurisdiction area) allowed select DPEs to conduct all flight instructor practical tests, including initial CFI. However, Ive heard rumours that the FAA revoked all DPE's (nationwide) ability to conduct any CFI initial test. I haven't actually heard or read anything official on this though. But, even if this were the case, I'm not sure what your doing would be considered an initial CFI.
Sigh, looks like I've created more questions then answered! Contact one of the friendly inspectors at your local FSDO. It's unlikeley that you'll get much other then opinion from a public forum.
Good luck with getting your CFI back!