The conquistadors knew this was Aztec practice. Several separate instances of Aztecs sacrificing and cannibalizing Spaniards were reported in Bernal Diaz’s contemporaneous “The True History of the Conquest of New Spain.”
https://en.wikipedia.org/wiki/Bernal_D%C3%ADaz_del_Castillo
Nice to see some modern independent evidence confirming the cannibal practices to refute the Aztec apologists.
That’s true. Bernal Diaz even recounts Cuauhtémoc threatening to eat the flesh of Cortéz with molé, which was apparently the preferred sauce for such occasions.