Mole negro technique — charring chiles and tortilla

Oaxaca, Mexico — specifically this charring technique is what defines the Central Valley and Sierra Norte mole negro tradition

The defining technique of mole negro is the deliberate charring of dried chiles (chilhuacle negro, mulato) and a piece of corn tortilla or dried bread until completely black. This blackening — often described as burning — provides the bitter, complex dark notes that make mole negro distinct from all other moles. The charred tortilla (or stale bread) acts simultaneously as a thickener and as a colour and flavour contributor. This technique is counterintuitive: it looks like a mistake but is essential.

Dark, bitter-complex, earthy — the char contributes a coffee-and-dark-chocolate note without actual coffee or chocolate being present