Though I would usually discourage vegetables in proximity to chili, one of the best Frito Chili Pies I've eaten was at a place in San Antonio called Cheesy Jane's (mediocre food otherwise). Their truly excellent version has fritos covered in very good chili, onions, and cheese. These are briefly heated under the broiler - then covered with shredded lettuce and chopped tomatoes (these are not heated). Quite delicious.