The Mexican dish of tortilla chips topped with cheese and chili is nachos. The basic version uses fried corn-tortilla triangles covered with melted cheese and often jalapeño peppers; modern versions may add meat, beans, salsa, guacamole, sour cream, or other toppings.
Nachos originated in 1943 in Piedras Negras, Coahuila, Mexico, just across the border from Eagle Pass, Texas. Restaurateur Ignacio “Nacho” Anaya reportedly improvised the snack when a group of American diners arrived and the regular cook was unavailable. He cut tortillas into triangles, added cheese and pickled jalapeños, heated them, and called the creation “Nacho’s Special.” “Nacho” is a familiar nickname for Ignacio.
Quesadillas and tostadas are different dishes: quesadillas center on a folded tortilla with filling, while tostadas are usually whole crisp tortillas with toppings. Chilaquiles also use tortilla pieces, but they are simmered or coated in salsa and commonly served as a breakfast dish rather than assembled as cheesy chips.