Nacho and Dog were the characters Taco Bell used to promote their kids' meals for a time. Nacho was a hyperactive orange cat, Dog was an intelligent, laid-back blue dog. In most of the ads, Nacho would attempt some insane stunt, while Dog would just sit on the couch reading a book and commenting on the proceedings. Their slogan was "Fetch that food!"
Fun trivia fact: Nacho was voiced by comedian Eddie Deezen, perhaps best known for voicing Mandark on Dexter's Laboratory. Dog was voiced by Rob Paulsen.