well there was just this post https://news.ycombinator.com/item?id=29960105 the subject of which was also a related article at the bottom of this one, seems more Tarrare was Domery lite.
Yes, it's about Charles Domery. I find his wikipedia article rather unbelievable. The mostly likely explanation by a mile seems that it's a joke or a hoax. It seems everything "known" about him comes from this[0] letter to a journal in 1799, purporting to quote another letter. The Tarrare story, likewise, seems to spring from a single article, in that case 1804 - those dates seem strangely close, if they're the two purported weirdest eaters in history—and both supposedly fought on the French side in the War of the First Coalition! I find it strange that the veracity of those reports isn't questioned or mentioned on those wikipedia pages.
How curious that both of the most incredibly voracious people ever both served Napoleon in the same time frame and their stories come from few isolated documents..