This was the first film that my mother saw in theaters, in the mid-70s. The film was a color live-action film and sure it was a children film because my mother had five years or less. She only remembers a scene that was very shocking for her. A child, perhaps the protagonist, was in a basement, a castle or a dungeon with a large group of witches trying to trick them into thinking he was a very powerful wizard. The witches discovered he was lying, then they caught him, put an apple in his mouth and placed him on a charcoal fire, turning like a suckling pig. My mother is not entirely sure but she believes the film could be American or English. The child was black hair and was dressed as a normal child of the 70s.
Do you know what movie would it be?