Trouble at the Dinosaur Cafe by Brian Moses, Garry Parsons

All is quiet in the Dinosaur Cafe until big bully Tyrannosaurus bursts in, demanding more than vegetarian fare. After he threatens to put all the herbivores into a dinosaur stew, they decide to retaliate and call in their secret weapon. And with big bully T-Rex cowering in the corner, the rest of the dinosaurs join in and tickle him.