How to redirect unauthorized access in AppController [CakePHP 3.X]

How do I redirect to my main page (www.example.com) when someone go on (http://ift.tt/1vDtnFb) from the AppController using 'unauthorizedRedirect' => false

I can't figure out the proper syntax to do what I want, even though I searched on the CakePHP Documentation.

Thanks for helping.