Frito pie is a dish popular in the Midwestern, Southeastern, and Southwestern United States, whose basic ingredients are chili, cheese, and corn chips (traditionally Fritos, hence the name). Additions can include salsa, refried beans, sour cream, onion, rice, or jalapeños. There are many variations and alternative names used by region. Frito pie can be prepared in a casserole dish, but an alternate preparation can be in a single-serve Fritos-type corn chip bag with various ingredients as toppings.

Source: Wikipedia