This tex-mex casserole is a well-spiced combination of ground beef, chopped vegetables, cheese, tomatoes, and pinto beans. Tortilla chips are layered with the ground beef mixture. If you like heat, use pepper jack cheese and add some finely chopped jalapeo or serrano peppers to the beef mixture. Or add some cayenne pepper. Serve this casserole with a tossed salad and cornbread, if you like.