something that has chile in it, or something cooked with chile as an ingredient (see Molina)
Alonso de Molina:
chillo. cosa que tiene axi, o cosa guisada con chilli. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 21r. col. 1. Thanks to Joe Campbell for providing the transcription.