Quesadillas originated in central Mexico and the southwest United States. The quesadillas commonly found in the United States are more like the Mexican sincronizadas rather than true Mexican quesadillas.
Americanized quesadillas, or sincronizadas, are made using a wheat flour tortillas that are layered and filled with cheese before being grilled or cooked to melt the cheese. Other stuffing, such as vegetables or meats, are commonly added. Traditional Mexican quesadillas are made of layered corn tortillas that are filled with cheese then cooked. These quesadillas also commonly contain squash flowers and pumpkin. A protein, such as chicken or beef, can also be added.