Cut the corn tortillas into ninths, place into a food processor and chop until fine. Add the flour, chili powder, cumin, salt and pepper. Blend until tortillas become the consistency of cornmeal. Set aside.
In a large saucepan, cook beef over medium heat until no longer pink; drain. Add the remaining ingredients. Bring to a boil. Reduce heat; simmer, uncovered, for 15-20 minutes or until macaroni is tender.