Oh, that's so cool you will visit my country. If you want to try local dishes you could try Empanadas de queso (cheese wraps-vegetarian) Sopaipillas (fried pumpkin dough-vegan) Humitas (corn based dish, don't know how to describe it but it tastes delicious-vegan) you can request these dishes in most restaurants, but in order to make sure they're 100 percent vegetarian you should say something like this: "Sin carne porfavor" or "No como carne ni pollo" (I don't eat meat nor chicken) or if you want to ask whether the dish contains any animal product, "esto tiene carne o algo animal? lo que pasa es que soy vegetariano/vegetariana" (does this have meat ? because I'm a vegetarian.
Hope you have fun!!!!!!!!!!