Also, William Seabrook.

In the 1920s, Seabrook traveled to West Africa and came across a tribe who partook in the eating of human meat. Seabrook wrote about his experience of cannibalism in his travel book Jungle Ways; however, he later admitted that the tribe had not allowed him to join in on the ritualistic cannibalism. Instead, he had obtained samples of human flesh by persuading a medical intern at the Sorbonne University to give him a chunk of human meat from the body of a man who had died in an accident.

…

Seabrook might have eaten human flesh also on another occasion. When his claim of having participating in ritualistic cannibalism turned out wrong (and he hadn’t yet dared reveal the Sorbonne story), he was much mocked for it. According to his autobiography, the wealthy socialite Daisy Fellowes invited him to one of her garden parties, stating “I think you deserve to know what human flesh really tastes like”. During the party, which was attended by about a dozen guests (some of them well-known), a piece of supposedly human flesh was grilled and eaten with much pomp. He comments that, while he never found out “the real truth” behind this meal, it “looked and tasted exactly” like the human flesh he had eaten before.