Petro's Chili & Chips is a small fast-food chain based in Knoxville, Tennessee, with several locations in Knoxville and other parts of East Tennessee.

History
Petro's got its start at the 1982 World's Fair in Knoxville. Joe and Carol Schoentrup, a married couple from Spokane, Washington, operated a food concession at the fair that served a combination of chili and corn chips that they dubbed the "Petro", a name derived from "petroleum" to honor the energy theme of the 1982 World's Fair. The concept was based on a snack item that had been sold at high school sports events in Omak, Washington, wherein chili and onions were poured into open bags of Fritos, to be eaten out of the bag. In the southwestern United States, similar snacks were known as "Frito pies" or "chili pies." For the World's Fair, the Schoentrups said they "gourmetized" this combination by adding cheddar and Monterey jack cheese, tomatoes, green onions, sour cream, and hot sauce. The product was very popular, selling 175,000 units over the six months of the Knoxville fair.

The Schoentrups also sold their product at the 1984 World's Fair in New Orleans. After the two world's fairs, the Schoentrups explored franchising their concept, and eventually sold the Petro's trademark and concept to brothers Dale and Keith Widmer. They established Petro's Chili & Chips outlets in food courts in shopping malls, starting with a location in Knoxville's West Town Mall. Franchising was added in 1992.

Products
Petro's primary product consists of corn chips topped with either meat-based or vegetarian chili, cheese, green onions, tomatoes, and sour cream, all served in a cup. Black olives, salsa, and Jalapeños are optional toppings. The menu also includes other variations in this basic item, as well as hot dogs, salads, stuffed baked potatoes, and soft-serve ice cream. Iced tea flavored with an orange slice is a Petro's specialty beverage.