Fantasticast Four #30: The Humanity Of Benjamin J. Grimm 10(ish)
Written by: Stan Lee (A rather nice writer)
Illustrated by: Jack Kirby (A quite noteworthy artist)
Inked by: Chic Stone (A somewhat nifty inker)
Lettered by: Art Simek (An occasionally neat letterer)
I guess this one counts, even though it's not a full return to human form.
One of the central conceits of this issue is that Diablo's alchemy is able to partially restore Ben's human form, reducing his monstrous exterior to little more than a severe skin complaint, whilst retaining a large portion of The Thing's strength. In the way of all such hokum, the reversion proves to be temporary, and appears to come with some kind of mental persuasion. Ben returns to his Thing form after only five pages.
What astonishes me is that Reed never went back to Diablo's alchemy to see if this temporary cure could be used as the base for a permanent one. Despite Diablo's nefarious intentions, he is able to partially reverse the transformation, and for an extended period of time. Unlike Reed's one-time use and temporarily effective cures, Diablo appears to be able to offer a workable solution that could be developed further. I guess this is counted as invalid due to it being created by a villain...
Check out our coverage of Fantastic Four #30 on our thirty-third episode: Bad Horse, Bad Horse, with special guest host David Walker