I'm not a Catalyst user at all, but I'm pretty sure you're not supposed to print anywhere in your code. Instead, you should be looking at

• How to set custom outgoing headers
• How to pass content around

As far as I can see, you should be doing something like $c->response->content('Hello World');
I assume there's something to set the content-type too, along the lines of $c->response->headers->header( 'Content-Type' => 'text/plain' );

Remember that you're working with an MVC framework. The View's sole responsibility is to transform data from one format to another. It's the Controller's job to actually send that data to the recipient.